Fix a Corrupted Windows User Profile

Signs of a corrupt profile

• Desktop is blank or shows default wallpaper unexpectedly
• "You have been logged on with a temporary profile" message
• Start menu and apps fail to open
• Personal files appear missing (they are still there)

Create a new local admin account

Settings → Accounts → Family & other users → Add someone else → I don't have sign-in info → Add a user without a Microsoft account. Make it an Administrator.

Copy profile data

Log into the new account. Navigate to C:UsersOldUsername. Copy Desktop, Documents, Downloads, Pictures, Music, AppDataRoaming (for app settings) to the new profile folder.

Fix via registry (advanced)

Regedit → HKLMSOFTWAREMicrosoftWindows NTCurrentVersionProfileList. Find the SID with a .bak suffix — swap the ProfileImagePath values between the .bak and the duplicate entry, then delete the duplicate.