Hi everyone, I am in the process of creating an MFC-based encryption software application, using Visual C++ .NET 2003. The program successfully encrypts and decrypts data on all versions of Windows just fine.

However, I run into a problem when trying to decrypt a file under a different version of Windows XP. For example, if I encrypt a file under Windows XP Service Pack 2, that same file can't be decrypted under Windows XP Service Pack 1, and vice-versa (it's as if the entire encryption/decryption process is completely different). I thought this might have to do with optimization options, but even with all optimizations disabled (and in Debug mode) the problem still exists. I tried both statically and dynamically linking to MFC, but the problem occurs in both situations.

I'm completely lost on what the problem might be. Any help would be most appreciated!