OS can't boot from hard disk

[Dibya Adhikari]

Hello I have two hard disk, one of them had lot of bad sectors so I merge the partition of that hard disk to try to fix it, my OS is installed in 1st hard disk, then after merging I restarted my computer but got boot Mgr missing error, I've checked my boot priority, tried to use both hard disk, I am confused my OS is in 1st HD and I formatted and merged second HD how did it affect my boot.

 

[Autocrat]

Messing around with HDDs is dangerous. A lot can go wrong.
Check out the MSFT support:
https://support.microsoft.com/en-us/kb/2622803

 

[Dibya Adhikari]

Sorry autocrat didn't mean to, I was just testing the buttons, didn't know I couldn't change the vote, anyway thanks for answer, I found out when you mark a partition as active this happens and thats what I did because after merging my 2nd HD was not showing. I will fix it from USB but just wanted to know why it happened.