FIX: GPF in VBDB300.DLL When Use ODBC to Connect to Oracle DB (124503)

SYMPTOMS

When trying to use ODBC with Visual Basic for Windows to get table information from an Oracle database, you may receive the following error message:

An error has occurred in your application...

When you choose the Close button, the following general protection (GP) fault error message appears:

VB caused a GPF in module VBDB300.DLL at 000A:1B0F

If you choose Ignore, your application may continue to run as expected.

CAUSE

It appears that this GP fault is caused within the file VBDB300.DLL by an incompatibility with specific network configurations. However, neither Microsoft nor Oracle have been able to duplicate this problem.

The problem has been reported to occur with both Oracle 6 and Oracle 7 on a variety of network software with a variety of network protocols. There is no one specific network or protocol that reproduces the problem.

WORKAROUND

The following workaround has been found to be successful if in addition to Visual Basic, you also have both Microsoft Access version 2.0 and the Microsoft Access 2.0/Visual Basic 3.0 Compatibility Layer installed:

In the VB.INI or <appname>.INI file (see page 148 of "Professional Features book 2"), add the following to the [ODBC] section (create one if needed):

   [ODBC]
   AttachableObjects='TABLE'

For more information about this .INI file entry, please see the Help menu in Microsoft Access version 2.0. Search for "INI Files," and select the "Customizing MSACC20.INI Setting" topic.

For additional information about the Compatibility Layer and how to get it, please see the following article in the Microsoft Knowledge Base:

113951 How to Obtain & Distribute the Compatibility Layer

MORE INFORMATION

Steps to Reproduce Problem

If you have a network configuration on which the problem does occur, the following piece of code will demonstrate the problem:

   Sub Command_Click()
      Dim db as Database
      Dim ds as Dynaset
      Set db = OpenDatabase("", 0, 0, "ODBC;")

      ' You will be prompted for the ODBC server information.
      Set ds = db.CreateDynaset("<tablename>")
      db.TableDefs.Refresh
   End Sub

The error occurs on the last line of code where the Refresh is trying to load the table information from the Oracle database into memory.