Is there a way to debug an .msi package that uses a .dll ??

A program I'm working on uses a serial check during the install via a .msi resourse .dll. Is it possible to 'live' debug the .dll with OllyDbg, or do I have to work on it via IDA Pro ??

Thanks!

You can do it with OllyDbg if you like. Easiest way would probably be to just attach to the installer process after you spin it up.

1. MsiBreak env var: http://msdn.microsoft.com/en-us/library/aa368264(VS.85).aspx
2. Wrapper DLL (needs replacing in the msi): http://blogs.msdn.com/astebner/archive/2005/03/07/388739.aspx

I've done a bunch of these either by just starting the installer, and grabbing the .dll from the TEMP dir that it puts it in, and if necessary, maybe writing a small app that calls the serial check function in the .dll so that you can step it that way.