An app runs well with Visual Studio debugger not by itself

[Windows 7 Application Compatibility episode 1]

I've tested an application built for Windows XP on Windows 7 machine.

The application failed silently on Windows 7 so I checked event log. There was no hint.

So, I downloaded application verifier on the machine and attached the application to it.

I didn't give any meaningful report. So I even attached the application to Windbg. But I cannot find where I should look into the application.

Later, we decided to build the application on Windows 7 with Visual Studio 2008 so we installed VS2008 on the machine.

And tried to build the application and managed to succeed in building it. And ran it in VS2008 with the debugger.

Hmm.... it succeeded in running.... as it worked on Windows XP.

But without Visual Studio? It failed again...! What's happening here?

The answer was "Application Verifier". Not until I deleted the applicaiton from Application Verifier and close Application Verifier to save the settings, I could run the application as it runs within VS.

My guess is the application has some system specific settings with it at the beginning and when I attached it to Verfier, it saved the first settings.

But by building again with VS 2008, the settings were updated. However, Application Verifer kicked in with old settings whenever the application was launched.

If you come across a similar problem, please try to build the application on Windows 7 without Application Verifier.