duplicate (?) files in my sims 4 folder

notphosie​  These files with DESKTOP at the end are probably the result of OneDrive syncing your Sims 4 data.  The OS won't allow two files with the same name in the same location, so OneDrive will add the computer name or something similar to the end of some files as necessary.

The files that get the extra characters in their names are supposed to be the older versions.  And the game can't use them with the modified names.  So if you're sure you're not missing any content, you can delete these files.  I would set aside anything in the saves folder though, just in case you realize later that you actually wanted an old save.

If you'd like to keep OneDrive from touching your Sims 4 data, please see the relevant section, whichever option you prefer, of the first post of this thread:

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