"Error loading operating system"

Hello,
For not so long now, I've been having this problem. I try to start Windows Vista and it says "Error loading operating system".
I've tried to rewrite the boot code, but that didn't work. I've also tried to do startup repair and it's saying that there's nothing wrong. System Restore is telling me that I don't have any restore points on the system drive.
Pretty much I've done everything I can think of except for reinstalling Windows.
What can I do to fix this problem?
 

My Computer

System One

  • Manufacturer/Model
    HP
    Memory
    2GB
    Screen Resolution
    1280x800
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