You'll need to use your installation disc/flashdrive to recover the situation.
Boot the media > Repair your computer > Repair startup.
Do the above line (all of it) three times.
There are several things that need fixing and the process only does one per boot.
If you don't have installation media, you can make a repair disc on any Windows PC using the same Windows version as you are trying to repair.
Control Panel > Backup and Restore > Create Repair Disc.