You installed classic right? and you insert the expansion disc and it doesn't ask you if you want to upgrade to the expansion version? is that what your saying?
I honestly never heard of that happening not being able to upgrade from classic to expansion verion after inserting the disc.
You can also download off the blizzard site if it doesn't work heres the guide,
D2 without cdnext time use this forum for future general install questions about d2 -
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