Alright so i've been playing around with the buttons hoping to press them in the right sequence to unlock the secret cow level or something. That pesky error pop-up that used to be blank now has text and reads:

"This application has encountered a critical error:

The file data is corrupt.

Program: C:\ProgamFiles(x86)\Diablo II\Game.exe
File: d2data.mpq

Press OK to terminate the application."

"OK"___"Cancel"


"OK" Closes the window and "Cancel" Brings up the "UNHANDLED EXCEPTION" pop up