I built an application in VS2005 and in dependency walker it shows that it was missing MSVCR80.dll, so I did a search on my machine and got one that was in the C:\Program Files\Microsoft Visual Studio 8\VC\cd\DLL\mipsiv\. But in dependency walker, the MSVCR80.dll was missing another dll called COREDLL.DLL, when I searched for this file on my machine I couldn't find it. I figured I was screwed.
But then I realized that I had multiple copies of MSVCR80.dll on my machine, the one in the above directory was 47 KB, there was another one in the C:\Windows\WinSxS\x80_Microsoft.VC80....... directory that was 612K, and it seemed that I had a lot of versions that were 612 KB. When I opened this in dependency walker it didn't need th COREDLL.DLL. So I was golden.