JSI Tip 5185. Windows 2000 issues 'Missing Operating System' error on restart?

When you start Windows 2000, you receive:

Missing Operating System

This can be the result of having the wrong partition marked as active.

If you suspect that this is the problem, you need to use Fdisk.exe to change the active partition. To do this, you need an DOS boot disk and the Fdisk.exe program. In tip 4011, we built a DOS boot disk, but without Fdisk.exe.

If you have access to a Windows 98 computer:

1. Insert a 3.5 inch diskette in the floppy drive.

2. Start / Run / Command / OK.

3. In the Command window, type: format a: /s and press Enter two times, where a: is the floppy drive letter.

4. Press Enter when prompted for a volume label.

5. Type n when prompted to format another diskette and press Enter.

6. Type copy c:\windows\command\fdisk.exe a: and press Enter.

7. Close the Command Windows.

To use Fdisk.exe.

1. Insert the diskette with Fdisk.exe into the Windows 2000 computer's floppy drive and start the computer.

2. At the A:\> prompt, type Fdisk.exe and press Enter.

3. Press Enter to enable large hard disk support. If prompted about NTFS, press Enter.

4. At the Enter choice item, type 2 and press Enter.

5. Type the partition number to mark as active and press Enter.

6. Press ESC.

7. Remove the diskette and restart Windows 2000.

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