Help!! Error loading operating system

[Rex123]

There is a problem with my old PC (Windows 7 x32, Intel duo core processor, 2.5 GB RAM) which was custom or assembled, it says 'Error loading operating system' and I have been trying to fix it for hours..
Earlier when this happened (A lot of times), I fixed it from the Repair option when I press F8 contineously, but when i keep on pressing it, nothing happens (System Repair Blackscreen does not come).
It happened when I pressed the restart button in my CPU when my PC was stuck for a long time, instead of waiting and manually restarting.
The biggest problem is that I LOST my Windows 7 CD. All I have now is just a USB with backup files.
When I put on the USB while booting, it says 'BOOTMGR is missing, Press Ctrl+Alt+Del to restart' but it shows the same thing when I restart.
When I pressed F10, It showed the Boot Option Menu, it had 3 options:
• SATA: Optiarc DVD RW AD-72203
• Realtek Boot Agent
• MBIC SS MMoser Baee Disk PMAP (That one is my USB)
These 3 didn't work either....
So, Please help me to find a way to fix it.
Ask me if you want any more information.
Thanks...

~Rex123

 

[Anshad Edavana]

Hi

Either a corrupted MBR or a failing hard drive can cause that error message. I would suggest ;

1. Replace the SATA data cable of the hard disk.

2. Run a "Long Test" with "Seatools for DOS" and verify disk's health condition.

http://www.sevenforums.com/tutorials/313457-seatools-dos-windows-how-use.html