Did you perform a Full Factory Restore or a Quick Factory Restore?
If your answer is Quick Factory Restore all you have to do is re-add the shares via the dashboard and be certain to spell them out as you did when you first made them and the files will still be there. However if your answer is a full factory restore I wouldn’t have much hope on recovering said files without spending money on professional data recovery services. I hate to say it but perhaps next time you should have a second or even third copy of your files. It is important to have backups. You could try recovering the files by pulling the hard drive out of the casing and using disk internals or recuva but because the disk was formatted I doubt you’ll get anything. Please take caution that doing so will void your warrenty.
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