Hi, AustinFournier
Thank you for using our Microsoft Community!
I understand from your message that you are looking for your old Wallpaper.
You can search Windows.old folder under system disk to check if your old wallpaper is here.
Or you can navigate to C:\Users\User name\AppData\Roaming\Microsoft\Windows\Themes\CachedFiles to check.
AppData is a hidden folder, you can click View>show>Hidden items under User name folder.
I hope the information provided is useful for you.
Best Regards
Silvia | Microsoft Community Support Specialist
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