Diablo 1 HD Hellfire Mod | Awake

Hello there. I'm new to this mod and this forum and I did not find a solution to my problem anywhere else.
I just installed Diablo 1 on Windows XP and installed the HD Mod after. Diablo I is patched to version 1.09b. When I try to start "Belzebub.exe" which is in the Diablo I directory, i get an error message:

"Belzebub.exe
This application has failed to start because the application configuration is incorrect. Reinstalling the application may fix this problem."

Does anybody know, how to fix this?
Thanks.

You install Open AL?

Yes, I installed OpenAL. I also copied the dll file from the archive in my system32 folder.
Edit: I installed openal again .. same result.

Install net.framework 3.5 and Microsoft Visual C++ 2010 Redistributable.

Thanks, it works now.

I wish I could say it's working, but no. I installed .NET framework and the Microsoft C++ redistributable as suggested, but still get the "missing mvar.dll" error. Do I need to uninstall the Hellfire mod and reinstall it? Or something else?

Thank you.

Coronary, it seems that you installed only patch 1.045 without full version v1.042. You must install v1.042 before patched.

Ps.
Hellfire is unnecessary.