d2game.dll is a file that belongs to the d2game.dll Module program. This file could be legitimate or a rogue file. The only reasonable way to tell is to find out from which directory the file originates. Even after you discover this, you may also find out that the file is either missing or has been corrupted in some way.
This happens with regularity when programs are installed or deleted from your computer. Error messages will accompany files that have problems. If you have received an error message for d2game.dll, then there may be a problem in your registry.
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