PRB: 80004005 Unspecified Error When Passing Disconnected Recordset from MTS to ASP

• Microsoft Data Access Components versions 2.0, 2.1, 2.1 (GA), 2.1 SP1, 2.1 SP2
• Microsoft Internet Information Server versions 4.0, 5.0
• Active Server Pages
• Microsoft Transaction Server 2.0

SYMPTOMS

When passing a disconnected ActiveX Date Objects (ADO) Recordset from a Component Object Model (COM) component inside a Microsoft Transaction Server (MTS) Server Package to Active Server Pages (ASP), you may receive one of the following error messages:

error '80004005'
Unspecified error
/xxx.asp, line x

-or- (with ASP error handling)

Error Number : 13 - Source : Microsoft VBScript runtime error - Type mismatch

-or- (after multiple tries)

Microsoft VBScript runtime error '800a0007'
Out of memory: 'obj.TestRS'
/xxx.asp, line x

CAUSE

An error occurs because the fields in the disconnected recordset have been defined as adVariant, and ADO cannot marshal certain data types within adVariant across process boundaries (in this case, between InetInfo and MTS). ADO marshaling cannot convert data of the following types when the field type is set to adVariant:

DBTYPE_BSTR = 8,
DBTYPE_IDISPATCH = 9,
DBTYPE_VARIANT = 12,
DBTYPE_IUNKNOWN = 13,
DBTYPE_ARRAY = 0x2000,
DBTYPE_BYREF = 0x4000,

// The following values exactly match VARENUM
// in Automation but cannot be used in VARIANT.
DBTYPE_I8 = 20,
DBTYPE_UI8 = 21,
DBTYPE_GUID = 72,
DBTYPE_VECTOR = 0x1000,
DBTYPE_FILETIME = 64,
DBTYPE_RESERVED = 0x8000,

RESOLUTION

When trying to pass values of the types mentioned above, such as strings (BSTR), you must declare those field types explicitly instead of using adVariant.

Example

    rs.Fields.Append "ID", adVariant 'this works since it is an Integer
    rs.Fields.Append "fname", adVarChar, 50
    rs.Fields.Append "lname", adVarChar, 50 

MORE INFORMATION

Steps to Reproduce Behavior

1. In Microsoft Visual Basic 6.0, create a new ActiveX DLL project.



2. Add the following references to the project:
   

   Microsoft Transaction Server Type Library
   Microsoft ActiveX Data Objects 2.x Library




3. Copy and paste the following code into the Class Module:

   
   Public Function TestRS() As Variant
       Dim rs As ADODB.Recordset
       Set rs = GetObjectContext.CreateInstance("ADODB.Recordset")
       rs.Fields.Append "ID", adVariant
       rs.Fields.Append "fname", adVariant
       rs.Fields.Append "lname", adVariant
       rs.CursorLocation = adUseClient
       rs.Open
       rs.AddNew
           rs(0) = 1
           rs(1) = "Yuri"
           rs(2) = "Lausberg"
       rs.Update
       Set TestRS = rs.Clone
       rs.Close
       Set rs = Nothing
       GetObjectContext.SetComplete
   End Function 




4. Set the Class Property MTSTransactionMode = 1 NoTransactions.



5. Compile the DLL.



6. Add the DLL to an MTS Server Package.



7. Copy and paste the following ASP script into a new ASP file.

   
   <%
     On Error Resume Next 
     Set obj = Server.Createobject("project1.class1")
     Set rs = obj.TestRS
     Response.Write rs(1)
     If Err.Number > 0 Then
       Response.Write "<B>Unable to read field value</B><P>"
       Response.Write "Error Number : "& Err.Number
       Response.Write " - Source : " & Err.Source
       Response.Write " -  " & Err.Description & "<P>"
     Else
       Response.Write rs(2)
     End If
     rs.Close
     Set rs = Nothing
   %> 




8. Request the ASP file from a browser, and the following error appears:

   Unable to read field value
   
   Error Number : 13 - Source : Microsoft VBScript runtime error - Type mismatch

Additional query words:

Keywords : kberrmsg kbADO kbASP kbCOMt kbMDAC kbMTS kbMTS200 kbIIS kbMDAC210 kbMDAC210SP2 kbMDAC250 kbCodeSnippet kbiis400 kbiis500
Version : WINDOWS:2.0,2.1,2.1 (GA),2.1 SP1,2.1 SP2; winnt:2.0,4.0,5.0
Platform : WINDOWS winnt
Issue type : kbprb