Compiled on Win 7 causes error when used on other Win 7 / XP machines

[Andrewvb]

Hi
I have an application written in VB6 which has been in development / use for many years.

I have upgraded to a Windows 7 machine and installed VB6 without any problems.

I can compile my application and run it OK but if I try to run on another Win 7 machine or XP (machines that run the app ok when compiled on an XP machine) I get an error!

The error is 13 - type mismatch, which does not make sense, it is simply a string with the connection details for a Data enviroment.

Nothing has changed in the app apart from the machine it is compiled on, compile it on the Win 7 machine and I have the problem, compile it on XP machine and it is OK

Any ideas?

[Nightwalker83]

Please post the code you are using so we can check it for you. Also, include which line is highlighted with the error when the code is run via the VB6 IDE?

[dilettante]

Is this Windows 7 SP1?

Win 7 SP1 Breaks ADODB Binary Compatibility

[Andrewvb]

Hi,
Thanks for your suggestions.
Just to be clear, there was no error when using the programme under the IDE or compiled on the Win 7 PC (SP1) that had VB6 installed. When the compiled programme was run on another Win 7 or XP machine the error appeared.

Removing service pack 1 resolved the problem! This is very annoying not least because it means not updating the development machine for fear of the problems reoccuring,

I would like to know which files are being affected by the SP1? as far as I can see, the project only references the same files as on the XP machine

[dilettante]

As far as I know this particular thing only involves ADO. This means msado15.dll and the series of typelibs that point to it (all msadoXX.tlb). The files are not the same. The Win7SP1 versions broke binary compatibility.

Just to be clear, there was no error when using the programme under the IDE or compiled on the Win 7 PC (SP1) that had VB6 installed. When the compiled programme was run on another Win 7 or XP machine the error appeared.

Yes, this is exactly the problem. Compiled on Win7SP1 works on Win7SP1 only.

It is also known that ADOX was broken in a similar manner later (msadox.dll) though in some SP levels of some versions of Windows there is a compatibility typelib (msadox28.tlb) you can compile against. ADOX can also be used late-bound though without a lot of work since its usage is typically very localized in programs.

As far as Win7SP1 though the ADO issue is the only new one I know about.


There are many, many other similar issues to be aware of when leaving the 2001 era (Windows XP) behind. Most of those are specialized though such as WinHelp support, the DHTMLEdit control, VB6 library for DirectX 7, etc. Anybody who waited this long to get up to speed on Win NT 6.x has a tough row to hoe. Most of the big changes were documented back in 2006 and MSDN links are going away day by day making the necessary info harder to come by.