Replace the registry Hives with the backups.
1. D/L the free
Rescue Kit Free Edition | PARAGON Software Group - free partition software, hard disk partitioning
2. Boot it up and select Normal Mode>File Transfer Wizard.
3. Browse to windows\system32\config and rename Default,Sam, Security,Software,System to
OldDefault,OldSam,OldSecurity,OldSoftware,OldSystem
( only rename the ones with no extensions - don't need to bother with any .LOG or .TM files ).
4. Browse to windows\system32\config\
regback copy the same hives to the paragon clipboard.
5, Browse back to windows\system32\config and paste them in.
Exit paragon boot disc, restart pc.