Notice: This website is an unofficial Microsoft Knowledge Base (hereinafter KB) archive and is intended to provide a reliable access to deleted content from Microsoft KB. All KB articles are owned by Microsoft Corporation. Read full disclaimer for more details.

PRB: Microsoft 32-Bit ODBC Drivers Cannot Be Used from 16-Bit Applications


View products that this article applies to.

This article was previously published under Q237388

↑ Back to the top


Symptoms

The Microsoft 32-bit ODBC drivers fail when called from a 16-bit application through the ODBC thunking layer. Particularly under Windows 95 and Windows 98, you will not be able to connect without the application failing.

↑ Back to the top


Cause

The Microsoft 32-bit ODBC drivers were not designed or tested to be used from 16-bit applications. Furthermore, drivers, such as the Access and SQL server drivers, create multiple threads, which thunking in Windows 95 and Windows 98 doesn't support.

↑ Back to the top


Resolution

If you need to access databases using the newer 32-bit ODBC drivers from a 16-bit application, you cannot do it directly. You will need to take the database access portion out of the 16-bit application. Build a brand new 32-bit application that will perform the database access. Then you can re-code your 16-bit application to use interprocess communication such as Sockets, DDE, and OLE Automation in order to transfer data to and from new 32-bit application.

As it might turn out to be too much work, perform the above steps only if you have huge 16-bit application and data access is only a small part of it. If you have a smaller 16-bit application, it is best to reprogram and rebuild the application with the 32-bit version of Visual C++.
The 16-bit SQL Server ODBC driver, which is included with SQL Server 6.5 can be used against SQL Server 7.0, although you will have some limitations, such not being able to use the new SQL 7.0 data types.

↑ Back to the top


Status

This behavior is by design.

↑ Back to the top


Keywords: KB237388, kbprb, kbdatabase

↑ Back to the top

Article Info
Article ID : 237388
Revision : 5
Created on : 12/5/2003
Published on : 12/5/2003
Exists online : False
Views : 370