Upgrade to EntireX Version 8 causes Error

I used to be able to call a version 7.3.3 EntireX workbench generated dll from VB6 (DCOM). After generating the dll using EntireX version 8, I am unable to call the generated dll from VB6. The error I get is:

This error is being caused by a parameter being defined as a string in VB6 and an N3 in the IDL from which the EntireX dll was generated. I am passing an empty string to the EntireX dll. When I pass a “0” instead of an empty string, there is no error. Note again, that this was not the case in version 7. The problem is that I have a few hundred dll’s where this might be a problem so changing my VB6 code is impractical. Is there a switch or setting available that will mimic the version 7 behaviour in version 8?

Did you rule out the Microsoft runtime being the source of the problem? see this for example:
Can you attach the VB source snippet and IDL?
Shmuel Coller

I dont think that the link provided is relevant to my issue because I am using VB 6 and this is not an issue with EntireX v7. The IDL is :

library 'Global':'Bracweb' is

program 'BPE001N1':'StdCodesEnq' is define data parameter
   	1 IP-USER-ID       	(A6)
   	1 IP-RESOURCE-ID   	(A6)
   	1 IP-FORM-NAME     	(A8)
   	1 IP-ACTION        	(A1)
   	1 IOP-SCROLL-DIR   	(A1)
   	1 IOP-BOF          	(A1)
   	1 IOP-EOF          	(A1)
   	1 IOP-OCCURS       	(N3)
   	1 IOP-CODE-TYPE	  	(A8)
   	1 IOP-DESC		  	(A32)
   	1 IOP-CODE		  	(A8)
   	1 OP-CODE-TYPE 	  	(A8/50) 	In Out
   	1 OP-RESOURCE-ID	(A6/50)
   	1 OP-DISP-ORDER		(N3/50)
   	1 OP-DESC			(A32/50)
   	1 OP-CODE			(A8/50)
   	1 OP-DEFAULT		(A1/50)
   	1 OP-ORIGINAL-CODE  (A8/50)
	1 OP-FIELD1         (A50/50)
	1 OP-FIELD2         (A50/50)
	1 OP-FIELD3         (A50/50)
	1 OP-FIELD4         (A50/50)
	1 OP-FIELD5         (A50/50)
   	1 ERR-TYPE 			(A1/5) 	
   	1 ERR-MESSAGE 		(A150/5) 	
   	1 ERR-TAB 			(N2/5) 	
   	1 ERR-PROGRAM 		(A8/5) 
   	1 ERR-FIELD 		(A20/5) 	

and the VB 6 code is:

Public Sub getCodes(Optional ipUserID As String = "", Optional ipResourceID As String = "", _
 Optional ipFormName As String = "BPE001N1", Optional ipAction As String = "", _
 Optional iopScrollDir As String = "", Optional iopBof As String = "", _
 Optional iopEOF As String = "", Optional iopOccurs As String = "", _
 Optional iopCodeType As String = "")
   Dim xmlNode                   As MSXML2.IXMLDOMElement
   Dim xmlAttrib                 As MSXML2.IXMLDOMAttribute
   Dim codetypeIN                As String * 8
   Dim iopDispOrder              As String
   Dim iopDesc                   As String * 32
   Dim IOPCODE                   As String * 8
   Dim OPEOF                     As String
   Dim opCodeType()              As String
   Dim OPRESOURCEID()            As String
   Dim opDispOrder()             As String
   Dim OPDESC()                  As String
   Dim OPCODE()                  As String
   Dim opDefault()               As String
   Dim OPORIGINALCODE()          As String
   Dim opField1()                As String
   Dim opField2()                As String
   Dim opField3()                As String
   Dim opField4()                As String
   Dim opField5()                As String
   Dim opErrorType()             As String
   Dim opErrorMessage()          As String
   Dim opErrorProgram()          As String
   Dim opErrorField()            As String
   Dim outDoc                    As MSXML2.DOMDocument40
   Dim menuObj                   As MSXML2.DOMDocument40
   Dim outXml                    As String
   'On Error GoTo errorHandle:
   Dim xmlGlobalNode             As MSXML2.IXMLDOMElement
   Dim xmlDatNode                As MSXML2.IXMLDOMElement
   Dim n                         As Long
   Dim oldType                   As String
   Set xmlNode = mvarXmlDom.selectSingleNode("//GLOBALS")
   codetypeIN = iopCodeType
   ReDim opCodeType(49) As String
   ReDim OPRESOURCEID(49) As String
   ReDim opDispOrder(49) As String
   ReDim OPDESC(49) As String
   ReDim OPCODE(49) As String
   ReDim opDefault(49) As String
   ReDim OPORIGINALCODE(49) As String
   ReDim opErrorType(4) As String
   ReDim opErrorMessage(4) As String
   ReDim opErrorTab(4) As String
   ReDim opErrorProgram(4) As String
   ReDim opErrorField(4) As String
   ipUserID = ""
   ipResourceID = ""
   ipAction = ""
   mvarExObj.ServerAddress = commonXml.ConnectString("ENTXBRAC")
   mvarExObj.StdCodesEnq ipUserID, ipResourceID, ipFormName, ipAction, _
                         iopScrollDir, iopBof, iopEOF, iopOccurs, _
                         codetypeIN, iopDispOrder, iopDesc, IOPCODE, _
                         opCodeType, OPRESOURCEID, opDispOrder, _
                         OPDESC, OPCODE, opDefault, OPORIGINALCODE, _
                         opField1, opField2, opField3, opField4, opField5, _
                         opErrorType, opErrorMessage, opErrorTab, _
                         opErrorProgram, opErrorField
End Sub

The line that causes the error is ‘mvarExObj.StdCodesEnq …’. This is the call to the EntireX generated dll. When the iopOccurs and iopDispOrder variables are changed from “” to “0”, the problem is resolved. Note that both these variables are defined as strings in VB 6 and that the IDL defines them as N3. Again, this works in EntireX version 7. So the problem seems to be that EntireX v8 does not tolerate blank strings for numeric variables.