Instructions
Download the latest game software update from the Blizzard website. Check that the patch is version number 1.12 or higher, then install the update.
Open the Play disc on the virtual drive by double-clicking it, then open the Diablo 2 directory on your computer in a separate window.
Click and drag the file named "D2Music.mpq" from the Diablo 2 disc to the Diablo 2 directory on your computer. Drag the file named "D2xMusic.mpq" if you are using the Diablo 2: Lord of Destruction play disc.
Rename the file "D2Music.mpq" to "Diablo II Music" and "D2xMusic.mpq" to "Diablo II Expansion Music" if you are using a Mac. Windows users may skip this step.