I just backed up my ipad to my pc, but can't find the backup. It is not in the AppData\Roaming\Apple Computer\MobileSync\Backup folder. How can I find it?

If you don't see the backup in %AppData%\Apple Computer\MobileSync\Backup then it is likely to be in %UserProfile%\Apple\MobileSync\Backup instead. The former is the original location, the other is used by the Microsoft Store version of iTunes.

I'd recommend backing up to both iTunes and iCloud so you have options when the time comes to restore. See also Archive iPhone/iPad backup in Windows - Apple Community

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