Some overlay programs can cause Blizzard games to crash.
Troubleshooting for game crashes with error "The application encountered an unexpected error"
Troubleshooting steps for Diablo II crash errors
Troubleshooting steps for if Warcraft II crashes when trying to start the game.
Antivirus software scans a computer's memory and storage to identify and eliminate viruses.
How to disable the Game DVR and Game Bar in Windows 10
Information regarding crashes accompanied by a Blue Screen
Troubleshooting for Blizzard Battle.net desktop app crashes.
How to obtain error logs for Blizzard games
Information on what to do if you receive an error message saying you are online with your own key in Diablo 2.