the pc had some issue so you did a factory reset, Yes?
this would have (hopefully) prompted you that proceeding will wipe all your data, did you do any backups?
it then would have either formatted the drive (low-level or quick format) then, from the Recovery partition, over-written all your data and Windows files stored on C:\ drive with the factory image.
I hate to be the bearer of bad news but Recuva is probably finding the filenames left-over but their matching data would have a high likelihood of being corrupted - which I think you are seeing.
Then add to that, since the factory reset, you have been surfing the web (at least to download Recuva) and the PC would have been updating, you may have install AV software - the list goes on.
If so, you have been corrupting the very data you are now trying to recover.