Change Active partition and boot problem

When you change your partition active to the another partition with no OS, your PC cannot be boot into OS. to fix it,  you can Try booting into the Windows 7 DVD / or usb booting windows 7.



when the option for installation of windows, select repair and open a Command Line, then type:

DISKPART
LIST DISK
SELECT DISK # (for Windows 7 disk)
LIST PARTITION
select partition # (for Windows 7 partition or MBR partition)
active
exit

done and restart your PC, Good luck