Common boot issues can be fixed by doing the following:
Method 1
Using a Windows boot disc, go to Startup Repair (do this 3-4 times, if necessary).
Method 2
If that doesn’t work try the Repair Option and this time choose Command Prompt, type:
BOOTREC /FIXMBR {enter}
BOOTREC /FIXBOOT{enter}
BOOTREC /SCANOS {enter}
BOOTREC /REBUILDBCD {enter}
Method 3
If it’s not successful or you receive No operating system found or Element not found messages, use diskpart and enter these commands:
DISKPART {enter}
LIST DISK {enter}
SELECT DISK N {enter}
LIST PARTITION {enter}
SELECT PARTITION N {enter}
ACTIVE {enter}
EXIT {enter}
Startup repair – Reboot
If there are still issues, try one more Startup repair and reboot.