Solving "DLL load failed: %1 is not a valid Win32 application." for Pygame

It could be due to the architecture of your OS. Is your OS 64 Bit and have you installed 64 bit version of Python? It may help to install both 32 bit version Python 3.1 and Pygame, which is available officially only in 32 bit and you won't face this problem.

I see that 64 bit pygame is maintained here, you might also want to try uninstalling Pygame only and install the 64 bit version on your existing python3.1, if not choose go for both 32-bit version.

Looks like the question has been long ago answered but the solution did not work for me. When I was getting that error, I was able to fix the problem by downloading PyWin32

I had installed Python 32 bit version and psycopg2 64 bit version to get this problem. I installed psycopg2 32 bit version and then it worked.

Had this issue on Python 2.7.9, solved by updating to Python 2.7.10 (unreleased when this question was asked and answered).

Another possible cause of similar issue could be wrong processorArchitecture in the cx_freeze manifest, trying to load x86 common controls dll in x64 process - should be fixed by this patch:

https://bitbucket.org/anthony_tuininga/cx_freeze/pull-request/71/changed-x86-in-windows-manifest-to/diff