Windows – Missing operating system

bioshard drivewindows 7

I have a problem with "Missing Operating system".
First the screen with Gigabyte Motherboard takes too long. About 1-2 minutes. After that it shows me the next screen who is black with the error "Missing operating system".
I mention that sometimes, if the Gigabyte screen takes 5-10 seconds it founds the hdd and problem is solved and the computer enter Windows.
I don't understand why sometimes my hdd is found and sometimes not.
What is the problem?

Best Answer

Well it could be one of the following problems:

  • The basic input/output system (BIOS) does not detect the hard disk.
  • The hard disk is damaged.
  • Sector 0 of the physical hard disk drive has an incorrect or malformed master boot record (MBR).

    Note Some third-party programs or disk corruption can damage an MBR.
  • An incompatible partition is marked as Active.
  • A partition that contains the MBR is no longer active.

My advice is to find your Windows 7 install DVD and boot from the DVD. Don't choose Install Now but choose Repair your Computer.

Here's a good tutorial on how to check your disk for errors and how to fix your MBR:

Missing Operating System: Windows 7

Just follow the steps in his post and your Computer should be fine. If none of the above work it's probably a hardware defect. If it's a hardware defect I would strongly suggest to backup all your DATA the next time you are able to boot into Windows 7.

Also what you can do the next time you are able to boot into Windows 7 is to check if your boot-drive is marked as active:

check this tutorial: How to Mark a Partition as Active in Windows 7

Another thing you could try is to simply restore your BIOS settings to its defaults (factory settings).

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