Question : Operating System Not Found -- Windows 2000 server

Our local network server running with windows 2000 server hangs and when i restarted it has given "Operating System Not Found" message.  Please help me in resolving it.

Answer : Operating System Not Found -- Windows 2000 server

Hi,

Try this,

Knowlege base article.

"Missing Operating System" Error Message When You Restart Windows 2000 Server

 SYMPTOMS
When you try to start your Microsoft Windows 2000 Server-based computer, you receive the following error message:

Missing Operating System
The startup process does not continue.
CAUSE
The incorrect partition is marked active.
RESOLUTION
To resolve this issue, you must change your computer's active partition. Fdisk.exe is a tool with which you can modify the active partition. You can run Fdisk.exe from a bootable 3.5-inch disk that was created in Microsoft Windows 98.

To change the active partition, follow these steps:

Create a Bootable 3.5-Inch Disk That Contains Fdisk.exe
On a computer running Windows 98, insert a blank 3.5-inch disk into the disk drive.
Click Start, and then click Run.
In the Run dialog box, type command, and then click OK.
At the command prompt, type:
format a: /s

Press ENTER two times.
When you are prompted to type a volume label, press ENTER.
When your are prompted to format another, type n, and then press ENTER.
Type the following command to copy the Fdisk.exe file to the 3.5-inch disk:
copy c:\windows\command\fdisk.exe a:

Press ENTER.
After the copy is completed, close command prompt.
Change the Active Partition
Insert the 3.5-inch disk that you created into the disk drive of the Windows 2000 Server-based computer.
Start the computer.
At the A:\> prompt, type:
fdisk.exe

Press ENTER.
Press ENTER to enable large hard disk support.NOTE: You may be prompted to enable large hard disk support on NTFS; if so, press ENTER to continue.


In the Enter choice selection, type 2, and then press ENTER.
Type the number of the partition to mark as active, and then press ENTER.
Press ESC.
Remove the 3.5-inch disk, and then restart the computer.