Application won't start - how to debug?

We just released a new version of one of our applications, and are hearing early reports that it won't run on a few customer's computers. This is a 32-bit Win32/MFC application that we have been shipping for about 5 or 6 years, so there is a history that the thing works. The problem I have is trying to get it running on the two computers. I can't reproduce the problem in-house, nor do I have any real access to the two computers in question. This much I do know - the InitInstance method is never called. I've checked it out in dependencywalker and everything looks OK (except for missing IEShims and wer.dll - but this is common, even in-house). What other tools do I have at my disposal to d开发者_如何转开发iagnose this problem?

Thanks for your help.

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When a program crashes during initialization, it will usually leave an entry in the windows application error log. (Control Panel -> Administrative Tools -> Event Viewer)

There should be something along the lines to "AppCrash" or perhaps "SideBySide"