Re: Moving whole game to different disc
@kenopopey I take it you've installed Sims 4 itself on D? If not, you'll need to uninstall the game through the EA App and reinstall onto D, specifically in a folder on D rather than on the root level of the drive.
To move the user data, you'll need to create a symbolic link:
If you have trouble with the process, please post the command you're using, the location where the symlink should be, and the path to the Sims 4 folder on D.