I would do the following
- Navigate to C:\Users\<username>
- Right click on Desktop and select Properties
- Click on the Security tab
- Click on Advanced
- The owner should be your user
- Permissions
- ALLOW SYSTEM Full Inherit from C:\Users<username> Applies to "This folder, subfolders and files
- ALLOW <Username> Full Inherit from C:\Users<username> Applies to "This folder, subfolders and files
- ALLOW Administrators Full Inherit from C:\Users<username> Applies to "This folder, subfolders and files
Most likely inheritence has been disabled, at the bottom if the bottom says "Enable inheritance" click that and the Destop folder should inherit permissions from C:\Users\<username> like it is supposed to.