Such as what?
Everything can be backed up if you know where to look.
I transferred to a whole new PC and everything is as I had it just fine. Do you mean aircraft hour logs, profiles etc?
Of course if the issue is with cloud save and you need to reset that, then you will lose some stuff (control presets, log book - but you can still access the hours flown). If you are going down this road of reinstalling Windows, I would start with a reinstall but NOT reset the cloud and see if that solved your problem first.