It is not possible to merge the progress of two or more games into one
How to resolve this error in Diablo II (2000)
Troubleshooting compatibility problems with classic games on newer computers.
What to do if you didn't get loot from Noth the Plaguebringer
Troubleshooting steps for Diablo II (2000) performance issues.
Information about this Netherstorm loremaster achievement
Troubleshooting steps to resolve a black screen in Diablo III