diff --git a/LSL2/STPROC/RDS_SERVICES.txt b/LSL2/STPROC/RDS_SERVICES.txt
index 339d8b8..bbbc533 100644
--- a/LSL2/STPROC/RDS_SERVICES.txt
+++ b/LSL2/STPROC/RDS_SERVICES.txt
@@ -1127,6 +1127,7 @@ Service CopyRDSLayerParameters(RDSNo)
 	StartTick = GetTickCount()
     MetricName = 'CopyRDSLayerParameters'
 	
+	ErrMsg = ''
 	If (RDSNo NE '') then
 		RunOrderNo  = Xlate('RDS', RDSNo, 'RUN_ORDER_NUM', 'X')
 		If (RunOrderNo GT 1) then
@@ -1172,15 +1173,17 @@ Service CopyRDSLayerParameters(RDSNo)
 				Next CopyRDSLayerKey
 			end
 		end else
-			Error_Services('Add', 'No previous run to copy RDS layer parameters from in ':Service:' service.')
+			ErrMsg = 'No previous run to copy RDS layer parameters from in ':Service:' service.'
 		end
 	end else
-		Error_Services('Add', 'RDSNo not supplied in ':Service:' service.')
+		ErrMsg = 'RDSNo not supplied in ':Service:' service.'
 	end
 	
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
     
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
+    
 end service
 
 
@@ -2446,21 +2449,3 @@ ClearCursors:
 	Next counter
 	
 return
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
diff --git a/LSL2/STPROC/REACTOR_SERVICES.txt b/LSL2/STPROC/REACTOR_SERVICES.txt
index 489f6d0..658909b 100644
--- a/LSL2/STPROC/REACTOR_SERVICES.txt
+++ b/LSL2/STPROC/REACTOR_SERVICES.txt
@@ -3768,7 +3768,7 @@ Service GetReactorAvailChamberCount(ReactNo)
 	StartTick = GetTickCount()
     MetricName = 'GetReactorAvailChamberCount'
 	
-	ErrMsg                = 'Error in ReactorServices -> GetReactorAvailChamberCount: '
+	ErrMsg = ''
 	AvailableChamberCount = 0
 	If ReactNo NE '' then
 		If RowExists('REACTOR', ReactNo) then
@@ -3778,16 +3778,19 @@ Service GetReactorAvailChamberCount(ReactNo)
 			AvailableChamberCount = ReactorCurrCapacity - ReactorCurrLoadCnt
 		end else
 			ErrMsg := 'Reactor ' : ReactNo : ' does not exist.'
-			Error_Services('Add', ErrMsg)
 		end
 	end else
 		ErrMsg := 'Reactor Number was null.'
-		Error_Services('Add', ErrMsg)
 	end
 	Response = AvailableChamberCount
 	
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then
+    	ErrMsg = 'Error in ReactorServices -> GetReactorAvailChamberCount: ':ErrMsg
+    	Error_Services('Add', ErrMsg)
+    end
 end service
 
 
diff --git a/LSL2/STPROC/SCAN_API.txt b/LSL2/STPROC/SCAN_API.txt
index 0c2131d..fa91e6f 100644
--- a/LSL2/STPROC/SCAN_API.txt
+++ b/LSL2/STPROC/SCAN_API.txt
@@ -263,6 +263,7 @@ API scan.ID.PATCH
     SRP_Stopwatch('Start', 'IDPatchResponseTime')
     // First confirm that this is a valid Scan ID.
     jsonScan    = Scan_Services('GetScansRow', ScanID, True$)
+    ErrMsg = ''
     If Error_Services('NoError') then
         // Confirm that all required data has been scanned before allowing the "accept" field to be updated.
         ParseResponse   = SRP_JSON(objResource, 'Parse', jsonScan)
@@ -293,7 +294,7 @@ API scan.ID.PATCH
                 end
             end else
                 ScanNotAcceptableReason = SRP_JSON(objResource, 'GetValue', 'scan.notAcceptableReason')
-                Error_Services('Add', ScanNotAcceptableReason)
+                ErrMsg = ScanNotAcceptableReason
             end
             SRP_JSON(objResource, 'Release')
         end else
@@ -324,6 +325,8 @@ API scan.ID.PATCH
     end
     LogData<6> = ResponseStatusCode
     Logging_Services('AppendLog', objLog, LogData, @RM, @FM, False$)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end api
 
 
@@ -438,3 +441,4 @@ return
 
 
 
+
diff --git a/LSL2/STPROC/SCAN_SERVICES.txt b/LSL2/STPROC/SCAN_SERVICES.txt
index 0447843..dcff130 100644
--- a/LSL2/STPROC/SCAN_SERVICES.txt
+++ b/LSL2/STPROC/SCAN_SERVICES.txt
@@ -214,19 +214,22 @@ Service GetScansRow(ScanID, ReturnJSON)
 	
 	ScansRow    = ''
 	
+	ErrMsg = ''
 	If ScanID NE '' then
 		ScansRow    = Database_Services('ReadDataRow', 'SCANS', ScanID)
 		If ReturnJSON EQ True$ then
 			ScansRow    = Scan_Services('ConvertMVScanToJSON', ScanID, ScansRow)
 		end
 	end else
-		Error_Services('Add', 'ScanID argument was missing in the ' : Service : ' service.')
+		ErrMsg = 'ScanID argument was missing in the ' : Service : ' service.'
 	end
 	
 	Response    = ScansRow
 	
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end service
 
 
@@ -239,14 +242,17 @@ Service SetScansRow(ScanID, ScansRow)
 	StartTick = GetTickCount()
     MetricName = 'SetScansRow'
 	
+	ErrMsg = ''
 	If (ScanID NE '') AND (ScansRow NE '') then
 		Database_Services('WriteDataRow', 'SCANS', ScanID, ScansRow)
 	end else
-		Error_Services('Add', 'ScanID or ScansRow argument was missing in the ' : Service : ' service.')
+		ErrMsg = 'ScanID or ScansRow argument was missing in the ' : Service : ' service.'
 	end
 	
 	EndTick = GetTickCount()
-    Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)	
+    Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end service
 
 
@@ -262,6 +268,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 	StartTick = GetTickCount()
     MetricName = 'ProcessScanData'
 	
+	ErrMsg = ''
 	If ( (ScanID NE '') AND (ScanJSON NE '') ) then
 		hScanJSON     = ''
 		ParseResponse   = SRP_JSON(hScanJSON, 'PARSE', ScanJSON)
@@ -300,7 +307,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 								If RowExists('LOT', LotId) then
 									TWLots = ScansRow<SCANS.TW_LOT_ID$>
 									Locate LotId in TWLots using @VM setting twPos then
-										Error_Services('Add', LotID : ' has already been added as a test wafer lot being used.')
+										ErrMsg = LotID : ' has already been added as a test wafer lot being used.'
 									end else
 										ScansRow<SCANS.TW_LOT_CHANGED$> = True$
 										LotCurrentOperation = Lot_Services('GetLotCurrOperationName', LotId)
@@ -316,14 +323,14 @@ Service ProcessScanData(ScanID, ScanJSON)
 													ScansRow<SCANS.TW_LOT_QTY$, twPos> = 1
 												end
 											end else
-												Error_Services('Add', LotID : ' does not have enough wafers to be used.')
+												ErrMsg = LotID : ' does not have enough wafers to be used.'
 											end
 										end else
-											Error_Services('Add', LotID : ' is not at a valid operation for use.')
+											ErrMsg = LotID : ' is not at a valid operation for use.'
 										end
 									end
 								end else
-									Error_Services('Add', LotID : ' is not a valid test wafer lot ID.')
+									ErrMsg = LotID : ' is not a valid test wafer lot ID.'
 								end
 								
 							Case Otherwise$
@@ -350,9 +357,9 @@ Service ProcessScanData(ScanID, ScanJSON)
 							Case EmployeeAuthorized NE True$
 								// Regardless of the not authorized reason, the scan data will be considered invalid.
 								EmployeeNotAuthorizedReason = {EMPLOYEE_NOT_AUTHORIZED_REASON}
-								Error_Services('Add', EmployeeNotAuthorizedReason)
+								ErrMsg = EmployeeNotAuthorizedReason
 							Case EmployeeActive NE True$
-								Error_Services('Add', 'Inactive employee.')
+								ErrMsg = 'Inactive employee.'
 							Case Otherwise$
 								ScansRow<SCANS.EMPLOYEE_ID$>    = {EMPLOYEE_ID}
 								
@@ -395,7 +402,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 									If (EmployeeAuthorized NE True$) AND ({EMPLOYEE_ID} NE '') then
 										// Regardless of the not authorized reason, the scan data will be considered invalid.
 										EmployeeNotAuthorizedReason = {EMPLOYEE_NOT_AUTHORIZED_REASON}
-										Error_Services('Add', EmployeeNotAuthorizedReason)
+										ErrMsg = EmployeeNotAuthorizedReason
 									end else                                       
 										*                                        If LoadLock EQ '' then LoadLock = 'NA'  ; // NA means Not Applicable.
 										ReactorID = ToolID[2, 999]
@@ -415,10 +422,10 @@ Service ProcessScanData(ScanID, ScanJSON)
 														ScansRow<SCANS.TOOL_ID$>        = ToolID
 														ScansRow<SCANS.LOAD_LOCK$>      = LoadLock
 													end else
-														Error_Services('Add', 'Invalid load lock value "':LoadLock:'".')
+														ErrMsg = 'Invalid load lock value "':LoadLock:'".'
 													end
 												end else
-													Error_Services('Add', 'A load lock side "L" or "R" is required for reactor ':ReactorID:'.')
+													ErrMsg = 'A load lock side "L" or "R" is required for reactor ':ReactorID:'.'
 												end
 											Case (LoadLockReq EQ False$)
 												If ScansRow<SCANS.LOCATION_ID$> NE '' then
@@ -433,17 +440,17 @@ Service ProcessScanData(ScanID, ScanJSON)
 										
 									end
 								Case ToolType _EQC 'Transfer'
-									Error_Services('Add', 'Tool type ':ToolType:' is not currently supported by the barcode application.')
+									ErrMsg = 'Tool type ':ToolType:' is not currently supported by the barcode application.'
 									// Code below may be implemented down the road.
 									// This is a transfer tool. Just update the scan resource.
 									*                                    ScansRow<SCANS.LOCATION_ID$>        = ''                                ; // Make sure the Location ID is cleared.
 									*                                    ScansRow<SCANS.CASSETTE_IDS$>       = ScansRow<SCANS.CASSETTE_IDS$, 1>  ; // Make sure only the first Cassette ID is tracked.
 									*                                    ScansRow<SCANS.TRANSFER_TOOL_ID$>   = ToolID
 								Case Otherwise$
-									Error_Services('Add', 'Tool type ':ToolType:' is not currently supported by the barcode application.')
+									ErrMsg = 'Tool type ':ToolType:' is not currently supported by the barcode application.'
 							End Case
 						end else
-							Error_Services('Add', ToolID : ' is not a valid tool ID.')
+							ErrMsg = ToolID : ' is not a valid tool ID.'
 						end
 						
 					Case ScanData[1, 2] EQ '1L'
@@ -461,7 +468,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 							ScansRow<SCANS.TRANSFER_TOOL_ID$>   = ''    ; // Make sure the Transfer Tool ID is cleared.
 							ScansRow<SCANS.LOCATION_ID$>        = LocationID
 						end else
-							Error_Services('Add', LocationID : ' is not a valid location ID.')
+							ErrMsg = LocationID : ' is not a valid location ID.'
 						end
 						
 					Case ScanData[1, 2] EQ '1B'
@@ -476,7 +483,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 							ScansRow<SCANS.BOAT_ID$>        = BoatID
 							ScansRow<SCANS.PL_NUMBER$>      = PLNo
 						end else
-							Error_Services('Add', ScanData : ' is not a valid boat ID.')
+							ErrMsg = ScanData : ' is not a valid boat ID.'
 						end
 					Case ScanData[1, 3] EQ 'PWD'
 						// Password/Signature scan. If the scan is not ready to be accepted or the password does
@@ -491,14 +498,14 @@ Service ProcessScanData(ScanID, ScanJSON)
 									ScansRow<SCANS.AUTHENTICATED$> = 1 
 								end else
 									ScansRow<SCANS.AUTHENTICATED$> = 0
-									Error_Services('Add', 'Invalid password for user ':EmployeeID:'.')
+									ErrMsg = 'Invalid password for user ':EmployeeID:'.'
 								end
 								ScansRow<SCANS.EMPLOYEE_CHANGED$> = True$
 							end else
-								Error_Services('Add', 'An employee ID must be scanned before scanning a password.')
+								ErrMsg = 'An employee ID must be scanned before scanning a password.'
 							end
 						end else
-							Error_Services('Add', 'Invalid password scanned.')
+							ErrMsg = 'Invalid password scanned.'
 						end
 					Case ScanData[1, 8] EQ 'OVERRIDE'
 						
@@ -565,7 +572,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 								end
 								
 							end else
-								Error_Services('Add', 'Selected Employee is not authorized to perform an override')
+								ErrMsg = 'Selected Employee is not authorized to perform an override'
 							end
 						end
 					Case ScanData[1, 2] EQ '5T'
@@ -651,11 +658,11 @@ Service ProcessScanData(ScanID, ScanJSON)
 								ScansRow<SCANS.CASSETTE_IDS$>   = CassetteID 
 							end
 						end else
-							Error_Services('Add', CassetteID : ' is not a valid Cassette ID.')
+							ErrMsg = CassetteID : ' is not a valid Cassette ID.'
 						end
 				End Case
 				
-				If Error_Services('NoError') then
+				If ErrMsg EQ '' then
 					// Process Scan row data here to determine the type of scan (i.e. Location, Pre-Epi + Load, or Unload).
 					ScanType     = ScansRow<SCANS.SCAN_TYPE$>                    
 					CassetteIDs  = ScansRow<SCANS.CASSETTE_IDS$>
@@ -682,7 +689,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 							LastCassScanned = CassetteIDs<0, NumCass>
 							CurrStage = Xlate('RDS', LastCassScanned, 'CURR_STAGE', 'X')
 							If CurrStage EQ 'UNLOAD' then
-								Error_Services('Add', '(':LastCassScanned:') Cassette is currently loaded on a tool and is ineligble for a location scan.')
+								ErrMsg = '(':LastCassScanned:') Cassette is currently loaded on a tool and is ineligble for a location scan.'
 							end
 							
 						Case ScanType EQ 'TOOL'
@@ -756,7 +763,9 @@ Service ProcessScanData(ScanID, ScanJSON)
 												CassNo      = Xlate('RDS', CassetteID, 'CASS_NO', 'X')
 												WOMatKey    = WONo:'*':CassNo
 												WOMatLocs   = Xlate('WO_MAT', WOMatKey, WO_MAT_INV_LOCATION$, 'X')
-												If Index(WOMatLocs,'PTI',1) else Error_Services('Add', 'Cassette ':CassetteID:' failed due to missing PTI.')                                      
+												If Index(WOMatLocs,'PTI',1) else
+													ErrMsg = 'Cassette ':CassetteID:' failed due to missing PTI.'
+												end
 											end else
 												// EpiPro RDS                                           
 												OutCassNos = Xlate('RDS', CassetteID, 'OUT_CASS_NO', 'X')
@@ -766,11 +775,13 @@ Service ProcessScanData(ScanID, ScanJSON)
 													CassNo      = OutCassNo
 													WOMatKey    = WONo:'*':CassNo
 													WOMatLocs   = Xlate('WO_MAT', WOMatKey, WO_MAT_INV_LOCATION$, 'X')
-													If Index(WOMatLocs,'PTI',1) else Error_Services('Add', 'Cassette ':CassetteID:' failed due to missing PTI.')                                                      
+													If Index(WOMatLocs,'PTI',1) else
+														ErrMsg = 'Cassette ':CassetteID:' failed due to missing PTI.'
+													end
 												Next OutCassNo
 											end     
 											
-											If Error_Services('NoError') then
+											If ErrMsg EQ '' then
 												If CurrStatus NE 'HOLD' then
 													If (EmployeeID NE '') then
 														*                                                    SupplInstAckReq         = Xlate('RDS', RDSNo, 'SUPPL_ACK_REQ'         , 'X')
@@ -1033,17 +1044,17 @@ Service ProcessScanData(ScanID, ScanJSON)
 																				end
 																			end else
 																				ScansRow<SCANS.SUPPLIER_LOT$> = ''
-																				Error_Services('Add', '(':CassetteID:') Supplier lot mismatch.')
+																				ErrMsg = '(':CassetteID:') Supplier lot mismatch.'
 																			end
 																		end else
 																			Scan_Services('AddNotAcceptableReason', 'Supplier lot scan required in order to complete a tool scan.')
 																		end
 																		
 																	end else
-																		Error_Services('Add', '(':CassetteID:') The first run must be completed using the OpenInsight user interface.')                                                                                                             
+																		ErrMsg = '(':CassetteID:') The first run must be completed using the OpenInsight user interface.'
 																	end                                               
 																end else
-																	Error_Services('Add', '(':CassetteID:') A pre-clean is required for this RDS. The OpenInsight user interface must be used to proceed.')
+																	ErrMsg = '(':CassetteID:') A pre-clean is required for this RDS. The OpenInsight user interface must be used to proceed.'
 																end                                        
 															Case CurrStage _EQC 'LOAD'
 																Action = 'LOAD'
@@ -1103,7 +1114,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 																					Scan_Services('AddNotAcceptableReason', ErrorMessage)
 																				end
 																			end else
-																				Error_Services('Add', 'Scanned tool ':ScanTool:' does not match the scheduled tool ':SchedTool:'. (':RDSNo:')')
+																				ErrMsg = 'Scanned tool ':ScanTool:' does not match the scheduled tool ':SchedTool:'. (':RDSNo:')'
 																			end
 																		end else
 																			Scan_Services('AddNotAcceptableReason', 'Test wafers are required to be logged with this run.')
@@ -1111,7 +1122,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 																	end else
 																		
 																		ScansRow<SCANS.SUPPLIER_LOT$> = ''
-																		Error_Services('Add', '(':CassetteID:') Supplier lot mismatch.')
+																		ErrMsg = '(':CassetteID:') Supplier lot mismatch.'
 																	end
 																end else
 																	Scan_Services('AddNotAcceptableReason', 'Supplier lot scan required in order to complete a tool scan.')
@@ -1195,12 +1206,10 @@ Service ProcessScanData(ScanID, ScanJSON)
 																								end
 																							end
 																						end else
-																							ErrorMessage = 'WO_MAT record was null.'
-																							Error_Services('Add', ErrorMessage)
+																							ErrMsg = 'WO_MAT record was null.'
 																						end
 																					end else
-																						ErrorMessage = 'Failure to read cassette record. ' :  Error_Services('GetMessage')
-																						Error_Services('Add', ErrorMessage)
+																						ErrMsg = 'Failure to read cassette record. ' :  Error_Services('GetMessage')
 																					end
 																				end
 																			end
@@ -1218,24 +1227,23 @@ Service ProcessScanData(ScanID, ScanJSON)
 																end                                                
 															Case CurrStage _EQC 'COMP'
 																Action = 'COMP'
-																Error_Services('Add', '(':CassetteID:") Cassette has already been FQA'd.")
+																ErrMsg = '(':CassetteID:") Cassette has already been FQA'd."
 															Case Otherwise$
 																Action = CurrStage
-																Error_Services('Set', '(':CassetteID:') The ':CurrStage:' is not currently supported by the barcode application.')
+																ErrMsg = '(':CassetteID:') The ':CurrStage:' is not currently supported by the barcode application.'
 														End Case
 													end else
 														Scan_Services('AddNotAcceptableReason', 'EmployeeID required to complete a tool scan.')                      
 													end
 												end else
-													Error_Services('Add', '(':CassetteID:') Process Error: cassette is on Hold and may not be signed off.')
+													ErrMsg = '(':CassetteID:') Process Error: cassette is on Hold and may not be signed off.'
 												end                                           
 											end
 										end else
-											Error_Services('Add', '(':CassetteID:') WMI/WMO cassette are not currently supported for tool scans. The OpenInsight user interface must be used in order to proceed.')
+											ErrMsg = '(':CassetteID:') WMI/WMO cassette are not currently supported for tool scans. The OpenInsight user interface must be used in order to proceed.'
 										end
 									end else
-										// Currently we are only supporting loading one cassette onto a tool at a time.
-										Error_Services('Add', '(':CassetteID:') Only one cassette can be loaded onto a tool at a time.')
+										ErrMsg = '(':CassetteID:') Only one cassette can be loaded onto a tool at a time.'
 									end
 								end
 								
@@ -1296,7 +1304,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 					End Case
 				end
 				// If the the scan data is valid, update the scan log before returning to the calling process.
-				If Error_Services('NoError') then
+				If ErrMsg EQ '' then
 					If Scan_Services('NoNotAcceptableReason') then              
 						ScansRow<SCANS.ACCEPTABLE$>             = True$
 						ScansRow<SCANS.NOT_ACCEPTABLE_REASON$>  = ''
@@ -1306,7 +1314,7 @@ Service ProcessScanData(ScanID, ScanJSON)
 					end                    
 				end else                    
 					ScansRow<SCANS.ACCEPTABLE$>             = False$
-					ScansRow<SCANS.NOT_ACCEPTABLE_REASON$>  = Error_Services('GetMessage')                           
+					ScansRow<SCANS.NOT_ACCEPTABLE_REASON$>  = ErrMsg                           
 				end
 				If ScanData NE '' then                   
 					ScansRow<SCANS.SCANNED_DATES$, -1>      = Date()
@@ -1314,25 +1322,21 @@ Service ProcessScanData(ScanID, ScanJSON)
 					ScansRow<SCANS.SCANNED_DATA$, -1>       = ScanData
 				end
 				ScansRow<SCANS.ACTION$> = Action
-				// Save error message if present as Database_Services will clear any errors.
-				ErrorMessage = ''
-				If Error_Services('HasError') then
-					ErrorMessage = Error_Services('GetMessage')
-				end
-				Database_Services('WriteDataRow', 'SCANS', ScanID, ScansRow, True$, False$, True$)
-				// Restore pre-existing error message if present.
-				If ErrorMessage NE '' then Error_Services('Add', ErrorMessage)                            
+				
+				Database_Services('WriteDataRow', 'SCANS', ScanID, ScansRow, True$, False$, True$)                           
 			end
 		end else
-			Error_Services('Add', 'Unable to parse the JSON scan data in the ':Service:' service.')
+			ErrMsg = 'Unable to parse the JSON scan data in the ':Service:' service.'
 		end
 		SRP_JSON(hScanJSON, 'Release')
 	end else
-		Error_Services('Add', 'ScanID or ScanJSON argument was missing in the ' : Service : ' service.')
+		ErrMsg = 'ScanID or ScanJSON argument was missing in the ' : Service : ' service.'
 	end
 	
 	EndTick = GetTickCount()
-    Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)	
+    Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end service
 
 
@@ -1344,6 +1348,7 @@ Service AcceptScan(ScanID, ScanJSON)
 	StartTick = GetTickCount()
     MetricName = 'AcceptScan'
 	
+	ErrMsg = ''
 	If ( (ScanID NE '') and (ScanJSON NE '') ) then
 		hBody         = ''
 		ParseResponse = SRP_JSON(hBody, 'PARSE', ScanJSON)
@@ -1376,7 +1381,7 @@ Service AcceptScan(ScanID, ScanJSON)
 							If Error_Services('NoError') AND SendStatus EQ 'Success' then
 								Result = 'Tencor Data Sent Successfully'
 							end else
-								Error_Services('Add', SendStatus)
+								ErrMsg = SendStatus
 							end
 							
 						Case ScanType _EQC 'LOCATION'
@@ -1481,8 +1486,7 @@ Service AcceptScan(ScanID, ScanJSON)
 							end
 							
 							IF Get_Status(errCode) THEN
-								ErrorMsg = 'Error calling obj_WO_Mat_Log("Create"). Error code: ':errCode
-								Error_Services('Add', ErrorMsg)
+								ErrMsg = 'Error calling obj_WO_Mat_Log("Create"). Error code: ':errCode
 							END else
 								NumCass = DCount(CassetteIDs, @VM)
 								If NumCass EQ 1 then
@@ -1545,8 +1549,7 @@ Service AcceptScan(ScanID, ScanJSON)
 												If Error_Services('NoError') then
 													Continue     = True$
 												end else
-													ErrorMessage = Error_Services('GetMessage')
-													Error_Services('Set', ErrorMessage)
+													ErrMsg = Error_Services('GetMessage')
 													Continue     = False$
 												end
 												If Continue then
@@ -1590,8 +1593,7 @@ Service AcceptScan(ScanID, ScanJSON)
 												If Error_Services('NoError') then
 													Continue     = True$
 												end else
-													ErrorMessage = Error_Services('GetMessage')
-													Error_Services('Set', ErrorMessage)
+													ErrMsg = Error_Services('GetMessage')
 													Continue     = False$
 												end
 												If Continue then
@@ -1627,8 +1629,7 @@ Service AcceptScan(ScanID, ScanJSON)
 												PSNo             = Xlate('RDS', RDSNo, RDS_PROD_SPEC_ID$, True$, 'X')
 												NewTestRunId     = Test_Run_Services('CreateTestRunRecord', TestRunType, 'R', Reactor, PSNo, RDSNo,Username ,  TestWaferLots, TestWaferLotQtys)
 												If Error_Services('HasError') then
-													ErrorMessage = Error_Services('GetMessage')
-													Error_Services('Set', ErrorMessage)
+													ErrMsg = Error_Services('GetMessage')
 													Continue = False$
 												end
 											end	
@@ -1645,10 +1646,10 @@ Service AcceptScan(ScanID, ScanJSON)
 											end
 										Case CurrStage _EQC 'COMP'
 											Action = 'COMP'
-											Error_Services('Set', '(':CassetteID:") Cassette has already been FQA'd.")
+											ErrMsg = '(':CassetteID:") Cassette has already been FQA'd."
 										Case Otherwise$
 											Action = CurrStage
-											Error_Services('Set', '(':CassetteID:') The ':CurrStage:' is not currently supported by the barcode application.')
+											ErrMsg = '(':CassetteID:') The ':CurrStage:' is not currently supported by the barcode application.'
 									End Case    
 								Case CassetteID EQ '' AND TestWaferLots NE ''
 									//Tool scan with ONLY test wafers being logged.
@@ -1661,12 +1662,10 @@ Service AcceptScan(ScanID, ScanJSON)
 										If NewTestRunId NE '' then
 											Result = 'Test run logged successfully'
 										end else
-											ErrorMessage = 'Error while logging creating test run.'
-											Error_Services('Set', ErrorMessage)
+											ErrMsg = 'Error while logging creating test run.'
 										end
 									end else
-										ErrorMessage = Error_Services('GetMessage')
-										Error_Services('Set', ErrorMessage)
+										ErrMsg = Error_Services('GetMessage')
 									end
 								Case Otherwise$
 									//null
@@ -1674,34 +1673,30 @@ Service AcceptScan(ScanID, ScanJSON)
 					End Case
 				end
 				
-				If Error_Services('NoError') then
+				If ErrMsg EQ '' then
 					ScansRow<SCANS.NOT_ACCEPTABLE_REASON$>  = 'This scan has already been accepted.'
 				end else 
-					ScansRow<SCANS.NOT_ACCEPTABLE_REASON$>  = Error_Services('GetMessage')                            
+					ScansRow<SCANS.NOT_ACCEPTABLE_REASON$>  = ErrMsg                            
 				end
 				ScansRow<SCANS.ACCEPTABLE$> = False$
 				If Assigned(Result) then ScansRow<SCANS.RESULT$> = Result
-				// Save error message if present as Database_Services will clear any errors.
-				ErrorMessage = ''
-				If Error_Services('HasError') then
-					ErrorMessage = Error_Services('GetMessage')
-				end
-				Scan_Services('SetScansRow', ScanID, ScansRow)
-				// Restore pre-existing error message if present.
-				If ErrorMessage NE '' then Error_Services('Add', ErrorMessage)    
+				
+				Scan_Services('SetScansRow', ScanID, ScansRow)   
 			end else
-				Error_Services('Add', 'The accepted.status field is missing from the JSON object in the ':Service:' service.')
+				ErrMsg = 'The accepted.status field is missing from the JSON object in the ':Service:' service.'
 			end
 			SRP_JSON(hBody, 'Release')
 		end else
-			Error_Services('Add', 'Unable to parse the JSON scan resource in the ':Service:' service.')
+			ErrMsg = 'Unable to parse the JSON scan resource in the ':Service:' service.'
 		end
 	end else
-		Error_Services('Add', 'ScanID or ScanJSON argument was missing in the ' : Service : ' service.')
+		ErrMsg = 'ScanID or ScanJSON argument was missing in the ' : Service : ' service.'
 	end
 	
 	EndTick = GetTickCount()
-    Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)	
+    Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end service
 
 //----------------------------------------------------------------------------------------------------------------------
@@ -1719,6 +1714,7 @@ Service ConvertMVScanToJSON(ScanID, mvScan, itemURL)
 	
 	mvScanChanged = False$
 	
+	ErrMsg = ''
 	If ScanID NE '' then
 		
 		If mvScan EQ '' then mvScan = Database_Services('ReadDataRow', 'SCANS', ScanID)
@@ -2172,17 +2168,19 @@ Service ConvertMVScanToJSON(ScanID, mvScan, itemURL)
 					Database_Services('WriteDataRow', 'SCANS', {SCAN_ID}, mvScan, True$, False$, False$)
 				end
 			end else
-				Error_Services('Add', 'Unable to create JSON representation in the ' : Service : ' service.')
+				ErrMsg = 'Unable to create JSON representation in the ' : Service : ' service.'
 			end
 		end
 	end else
-		Error_Services('Add', 'ScanID argument was missing in the ' : Service : ' service.')
+		ErrMsg = 'ScanID argument was missing in the ' : Service : ' service.'
 	end
 	
 	Response    = jsonScan
 	
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end service
 
 //----------------------------------------------------------------------------------------------------------------------
@@ -2421,3 +2419,5 @@ return
 
 
 
+
+
diff --git a/LSL2/STPROC/SCHEDULE_SERVICES.txt b/LSL2/STPROC/SCHEDULE_SERVICES.txt
index cad728b..f8887da 100644
--- a/LSL2/STPROC/SCHEDULE_SERVICES.txt
+++ b/LSL2/STPROC/SCHEDULE_SERVICES.txt
@@ -805,9 +805,9 @@ end service
 Service GetCurrentEvent(ReactNo)
 	StartTick = GetTickCount()
     MetricName = 'GetCurrentEvent'
-    ErrorMsg = ''
 	
 	SchedDetKey = ''
+	ErrorMsg = ''
 	If ReactNo NE '' then
 		CurrDTM  = Datetime()
 		Query    = 'SELECT SCHED_DET_NG WITH REACT_NO EQ "':ReactNo:'" AND WITH EVENT_COMP NE 1 BY START_DTM'
@@ -819,7 +819,7 @@ Service GetCurrentEvent(ReactNo)
 			ReadNext SchedDetKey else EOF = True$
 			Response = SchedDetKey
 		end else
-			ErrorMsg = 'Error in service ':Service:' module. Error code ':errCode
+			ErrorMsg = 'Error in service ':Service:' module. Error code ':errCode 
 		end
 		GoSub ClearCursors
 	end
@@ -827,17 +827,14 @@ Service GetCurrentEvent(ReactNo)
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
     
-    If ErrorMsg NE '' then
-        Error_Services('Add', ErrorMsg)
-    end
-    
+    If ErrorMsg NE '' then Error_Services('Add', ErrorMsg)
 end service
 
 Service CurrentEventIsBlock(ReactNo)
 	StartTick = GetTickCount()
     MetricName = 'CurrentEventIsBlock'
-    ErrorMsg = ''
 	
+	ErrorMsg = ''
 	If ReactNo NE '' then
 		CurrentSchedDetKey = Schedule_Services('GetCurrentEvent', ReactNo)
 				
@@ -861,18 +858,15 @@ Service CurrentEventIsBlock(ReactNo)
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
     
-    If ErrorMsg NE '' then
-        Error_Services('Add', ErrorMsg)
-    end
-    
+    If ErrorMsg NE '' then Error_Services('Add', ErrorMsg)
 end service
 
 Service GetNextEvent(ReactNo)
 	StartTick = GetTickCount()
     MetricName = 'GetNextEvent'
-	ErrorMsg = ''
 	
 	SchedDetKey = ''
+	ErrorMsg = ''
 	If ReactNo NE '' then
 		CurrDTM  = Datetime()
 		Query    = 'SELECT SCHED_DET_NG WITH REACT_NO EQ "':ReactNo:'" AND WITH EVENT_COMP NE 1 BY START_DTM'
@@ -894,7 +888,7 @@ Service GetNextEvent(ReactNo)
 				end
 			end	
 		end else
-			ErrorMsg = 'Error in service ':Service:' module. Error code ':errCode
+			ErrorMsg = 'Error in service ':Service:' module. Error code ':errCode  
 		end
 		GoSub ClearCursors
 	end
@@ -902,10 +896,7 @@ Service GetNextEvent(ReactNo)
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
     
-    If ErrorMsg NE '' then
-        Error_Services('Add', ErrorMsg)
-    end
-    
+    If ErrorMsg NE '' then Error_Services('Add', ErrorMsg)
 end service
 
 Service GetEngagedEvent(ReactNo)
@@ -957,9 +948,9 @@ end service
 Service NextEventIsSamePsn(ReactNo)
 	StartTick = GetTickCount()
     MetricName = 'NextEventIsSamePsn'
-	ErrorMsg = ''
 	
 	Response = False$
+	ErrorMsg = ''
 	If ReactNo NE '' then
 		CurrentSchedDetKey = Schedule_Services('GetCurrentEvent', ReactNo)
 		
@@ -1005,17 +996,14 @@ Service NextEventIsSamePsn(ReactNo)
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
     
-    If ErrorMsg NE '' then
-        Error_Services('Add', ErrorMsg)
-    end
-    
+    If ErrorMsg NE '' then Error_Services('Add', ErrorMsg)
 end service
 
 Service NextEventIsBlock(ReactNo)
 	StartTick = GetTickCount()
     MetricName = 'NextEventIsBlock'
-    ErrorMsg = ''
 	
+	ErrorMsg = ''
 	If ReactNo NE '' then
 		NextSchedDetKey = Schedule_Services('GetNextEvent', ReactNo)
 				
@@ -1039,10 +1027,7 @@ Service NextEventIsBlock(ReactNo)
 	EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
     
-    If ErrorMsg NE '' then
-        Error_Services('Add', ErrorMsg)
-    end
-    
+    If ErrorMsg NE '' then Error_Services('Add', ErrorMsg)
 end service
 
 //----------------------------------------------------------------------------------------------------------------------
diff --git a/LSL2/STPROC/SUPPLEMENT_SERVICES.txt b/LSL2/STPROC/SUPPLEMENT_SERVICES.txt
index 7b9766b..2651e83 100644
--- a/LSL2/STPROC/SUPPLEMENT_SERVICES.txt
+++ b/LSL2/STPROC/SUPPLEMENT_SERVICES.txt
@@ -456,6 +456,7 @@ Service AcknowledgeSupplement(SupplID, EntryUser)
 	StartTick = GetTickCount()
     MetricName = 'AcknowledgeSupplement'
     
+    ErrMsg = ''
     If ( (SupplID NE '') and (EntryUser NE '') ) then
         OldRec = Xlate('SUPPLEMENTS', SupplID, '', 'X', '')
         If OldRec NE '' then
@@ -469,19 +470,21 @@ Service AcknowledgeSupplement(SupplID, EntryUser)
                 Supplement_Services('LogSupplementChange', NewRec, 'Acknowledged', EntryUser)
             end else
                 Response = FALSE$
-                Error_Services('Add', 'Error editing Supplement record.')
+                ErrMsg = 'Error editing Supplement record.'
             end
         end else
             Response = FALSE$
-            Error_Services('Add', 'Record does not exist.')
+            ErrMsg = 'Record does not exist.'
         end
     end else
         Response = FALSE$
-        Error_Services('Add', 'SupplID or EntryUser was missing in the ' : Service : ' service.')
+        ErrMsg = 'SupplID or EntryUser was missing in the ' : Service : ' service.'
     end
     
     EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end service
 
 
@@ -501,6 +504,7 @@ Service UnacknowledgedSupplementCheck(LotType=LOTTYPES, LotID, Stage=STAGES)
     
     UnackList = ''
     Response  = False$
+    ErrMsg = ''
     If ( (LotType NE '') and (LotID NE '') and (Stage NE '') ) then    	    
 		KeyList  = ''
 		Query    = ''
@@ -518,23 +522,25 @@ Service UnacknowledgedSupplementCheck(LotType=LOTTYPES, LotID, Stage=STAGES)
 							If AckField NE True$ then UnackList<-1> = Key							
 						Next Key
 					end else
-						Error_Services('Add', 'Error in ':Service:' service. Error opening SUPPLEMENTS table.')
+						ErrMsg = 'Error in ':Service:' service. Error opening SUPPLEMENTS table.'
 					end
 				end
 			end else
-				Error_Services('Add', 'Error in ':Service:' service. Error calling Btree.Extract')
+				ErrMsg = 'Error in ':Service:' service. Error calling Btree.Extract'
 			end
 		end else
-			Error_Services('Add', 'Error in ':Service:' service. Error opening SUPPLEMENTS dictionary.')
+			ErrMsg = 'Error in ':Service:' service. Error opening SUPPLEMENTS dictionary.'
 		end
     end else
-        Error_Services('Add', 'LotType, LotID, or Stage was missing in the ' :  Service : ' service.')
+        ErrMsg = 'LotType, LotID, or Stage was missing in the ' :  Service : ' service.'
     end
     
     If UnackList NE '' then Response = UnackList
     
     EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end service
 
 
@@ -552,6 +558,7 @@ Service LogSupplementChange(SupplementRec, EditEvent, EntryUser)
 	StartTick = GetTickCount()
     MetricName = 'LogSupplementChange'
 
+    ErrMsg = ''
     If ( (SupplementRec NE '') and (EditEvent NE '') and (EntryUser NE '') ) then
         SupplementText = SupplementRec<SUPPLEMENTS_SUPPL_TEXT$>
         LotType        = SupplementRec<SUPPLEMENTS_LOT_TYPE$>
@@ -565,11 +572,13 @@ Service LogSupplementChange(SupplementRec, EditEvent, EntryUser)
         End Case
         
     end else
-        Error_Services('Add', 'LotType, LotID, or Stage was missing in the ' :  Service : ' service.')
+        ErrMsg = 'LotType, LotID, or Stage was missing in the ' :  Service : ' service.'
     end
     
     EndTick = GetTickCount()
     Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then Error_Services('Add', ErrMsg)
 end service
 
 
@@ -670,3 +679,4 @@ Service SendNotifications(RDSList, EditEvent, Instructions, EntryUser)
 	
 end service
 
+
diff --git a/LSL2/STPROC/WO_MAT_SERVICES.txt b/LSL2/STPROC/WO_MAT_SERVICES.txt
index 373701b..34b1b4c 100644
--- a/LSL2/STPROC/WO_MAT_SERVICES.txt
+++ b/LSL2/STPROC/WO_MAT_SERVICES.txt
@@ -447,37 +447,43 @@ Service CassetteIsLastInWo(WoMatKey)
 	
 	IsLastInWo = False$
 	
+	ErrMsg = ''
 	If Unassigned(WoMatKey) or WoMatKey EQ '' or RowExists('WO_MAT', WoMatKey) NE True$ then
-		Error_Services('Add', 'invalid WO_MAT key')
+		ErrMsg = 'invalid WO_MAT key'
 	end
 	
 	WO = Field(WoMatKey, '*', 1)
 	If WO EQ '' then
-		Error_Services('Add', 'WO# not found in WO_MAT record')
+		ErrMsg = 'WO# not found in WO_MAT record'
 	end
-	If Error_Services('NoError') and Num(WO) EQ False$ then
-		Error_Services('Add', 'WO# is not numeric')
+	If ErrMsg EQ '' and Num(WO) EQ False$ then
+		ErrMsg = 'WO# is not numeric'
 	end
 	
 	CassNo = Field(WoMatKey, '*', 2)
-	If Error_Services('NoError') and CassNo EQ '' then
-		Error_Services('Add', 'Cassette# not found in WO_MAT record')
+	If ErrMsg EQ '' and CassNo EQ '' then
+		ErrMsg = 'Cassette# not found in WO_MAT record'
 	end
-	If Error_Services('NoError') and Num(CassNo) EQ False$ then
-		Error_Services('Add', 'Cassette# is not numeric')
+	If ErrMsg EQ '' and Num(CassNo) EQ False$ then
+		ErrMsg = 'Cassette# is not numeric'
 	end
 	
-	If Error_Services('NoError') then
+	If ErrMsg EQ '' then
 		WoMatKeys = Xlate('WO_LOG', WO, WO_LOG_WO_MAT_KEY$, 'X')
-		If Error_Services('NoError') and WoMatKeys NE '' then
+		If WoMatKeys NE '' then
 			TotalCassettes = DCount(WoMatKeys, @VM)
 			IsLastInWo = TotalCassettes EQ CassNo
+		end else
+			ErrMsg = 'WO_MAT keys not found in WO_LOG for WO ':WO
 		end
 	end
 	
-	If Error_Services('HasError') then
-		ErrMsg = Error_Services('GetMessage')
-		
+	Response = IsLastInWo
+	
+	EndTick = GetTickCount()
+    Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
+    
+    If ErrMsg NE '' then
 		LogData = ''
 		LogData<1> = LoggingDtm
 		LogData<2> = WOMatKey
@@ -488,11 +494,6 @@ Service CassetteIsLastInWo(WoMatKey)
 		
 		Error_Services('Add', ErrMsg)
 	end
-	
-	Response = IsLastInWo
-	
-	EndTick = GetTickCount()
-    Mona_Services('QueueLatencyAndCountMetrics', MonaResource, MetricName, StartTick, EndTick)
     
 end service
 
@@ -697,3 +698,4 @@ Service VerifyWOLogWOMatKeyColumn(WOMatKey)
 end service
 
 
+