I am using Vista and the computer just restarted for no reason. The problem though the computer will not start. I am at a black screen with the message that the file windows\system32\winload.exe is missing or corrupt. The error code is 0xc000000f. I don't know what to do. The computer is asking for the startup disc. I did not receive one when I purchased my computer. I am lost as to what to do.
Sounds like a corrupted file system. You can use a Windows 7 disc to get to the Recovery Console and run chkdsk.
You can download a X86 (32bit) or X64 (64 bit) from here: Download Windows 7 ISO (Official 32-bit and 64-bit Direct Download Links)
Burn it to a DVD using ImgBurn at 4X speed (or the slowest you can get). Boot the DVD, take the Repair Path: How to Boot to the System Recovery Options in Windows 7
From the Command Prompt, enter chkdsk /f and press Enter. Let that complete, remove the DVD and reboot, see if that fixed the problem.
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