Restore to factory settings

I've reset before, but for some reason this time I can't seem to restore.  I've copied files both to USB and to a DVD.  Tried both media with same results.  Every time I try to rest it goes through the motions showing that it goes to 2% and then stops.  Then I get an error message "There was a problem resetting your PC.  No changes were made."  If anyone has a suggestion I would greatly appreciate it.  Thank you in advance.