Here are a few things I would recommend trying in the order I’ve listed them below:
BEFORE DOING EACH STEP ENSURE THIS STEP IS DONE
via Task Manager (ctrl & shift & escape) force stop all instances of:
Battle.net
Battle.net Update Agent
Agent.exe
Documents > Diablo IV > LocalPrefs.txt
change “Adapter” value from “0” to “1”
change “DisableChromaEffects” from “0” to “1”
save file > close file > relaunch battle.net + game
If this does get you into the game, but the game is using the wrong graphics adapter in the graphics settings in game… then you have 2 options:
You can disable on board graphics in bios or in device manager.
If you’re using a laptop disabling internal graphics may cause issues.
if this does not work, try renaming the LocalPrefs.txt to another name like LocalPrefs.old forcing the game to create a new file.
Battle.net > top left drop down > settings
“On Game Launch” > Exit Battle.net Completely
Battle.net > bottom left settings cog next to “Play”
Game Settings > Diablo IV drop down menu
Check box Additional command line arguments
put this text into the box > “-bypassgpudrivercheck” without the quotes
Hit Done
There’s a possibility Battle.net files are corrupted and these are not usually deleted when you uninstall the game or Battle.net.
This will force new Battle.net files without a reinstall. This is not the same folder where the LocalPrefs.txt is located.
Task Manager step again from above before doing this
https://us.battle.net/support/en/article/34719