Make sure to backup your save files. If possible, transfer them to a different hard drive or an external device (for example, SD card). Saves are located here: %userprofile%\Documents\The Witcher 3\gamesaves
Disable Cloud Saves feature for The Witcher 3: Wild Hunt if you have it enabled.
Uninstall The Witcher 3: Wild Hunt.
Remove:
The Witcher 3 folder in your client’s directory (Steam, GOG, EGS)
The Witcher 3 folder from here: %userprofile%\Documents\
Restart your PC.
Install The Witcher 3: Wild Hunt again. Do not install any mods!
If you install the game on the same partition as you have the Operating System installed, ensure that the game isn’t blocked by Windows permissions settings. Install it on the drive root, not nested in some folders. Example path after installation: C:\Steam\steamapps\common\The Witcher 3.
If the issue you encountered is technical (game crashing, not launching, etc.):
Run the game and see if it helped with the issue you encountered.
Copy your save files to the newly created The Witcher 3 folder in the location from step #1.
If the issue you encountered is gameplay-related (e.g. issues with quest progression):
Copy your save files to the newly created The Witcher 3 folder in the location from step #1.
Run the game and see if it helped with the issue you encountered.
