Win7 system blue screen prompt c000021a unknown hard error how to do

1, first of all you can start with Win PE starts, and then use Disk Utility to check the hard disk partition table for errors or modified, and then try to fix it The boot MBR of the hard disk. Then restart your computer to see if the problem is still there.

2, you can also try to install the system, most unknown hard error error, reinstall the system can be solved.

3. Check the hard drive data cable or replace the hard drive test. If the problem persists after reinstalling the system, it is very likely that the problem is on the hardware.

4, there is a more common situation, that is, we can reinstall the system but can solve the problem, but it will not happen long after the problem will occur, like this situation is mostly hard disk bad cluster, you can try to use The hard disk repair software first fixes the hard disk test, if it is still not recommended to replace the hard disk.