The most terrifying startup message is "Missing Operating System." You can check a few key items to ensure that this problem isn't serious, or learn how to resolve the issue by using the Windows Recovery Menu.
- [Narrator] Nothing instills terror like a startup message that reads, "Missing Operating System." This error doesn't directly imply that Windows has packed up its bags and taken holiday somewhere tropical. No, this beast of a message is a specific startup error, and quite a few situations can rouse that monster. In this movie, I go over the different types of messages you can see when you start your computer and how to resolve them. The steps involve using the startup repair tool as well as using the command prompt to fix a boot drive's master boot record.
In the PC startup process, the firmware's last duty is to scan for and load an operating system from one of the system's mass storage devices. A bootable storage device is one with an operating system installed. So when the firmware can't locate such media, it displays one of the vile messages you see here. To review the list of storage media and see what the firmware sees when it tries to hand off the ball, you can do one of two things. The first is to visit the Windows Recovery Menu.
Accessing the recovery menu is covered in another movie but here's a shortcut. Click the Start button. Choose Power. Press and hold the Shift key. And click Restart. The computer restarts and runs the Windows Recovery Menu. To review the boot devices to see what the firmware sees, on this screen you would choose the option Use a Device. But on this screen it doesn't show up. That's because this PC lacks the secure boot technology feature.
So on this system, you would have to use the second trick. And that's to press the F12 key or the F10 key when the system first starts. Then you'll see the list of boot devices. In both cases, what you're looking for is a bootable drive, something beyond the PC's main boot disk with which you can start the system. For example, you would use the system recovery disk which is covered in another movie which would bring you right to this prompt because that's where you want to end up. The process of repairing the system's main boot disk involves clicking the Troubleshoot button, Advanced options, and Startup Repair.
The system restarts and attempts to repair itself. Now, nothing is wrong with this PC so nothing will be repaired, I hope. I sign in with my main account. And, either there was something wrong that it couldn't fix but in most cases what this means is that nothing was wrong. No problems were found. Click Advanced Options to return to the Windows Recovery Menu. Otherwise, you would see directions on the screen that would tell you what to do next, implement a suggestion, follow a solution, something along those lines.
Another thing you can try to do is to rebuild the main storage device's master boot record or MBR. The system repair tool might be able to attempt this process as well, but you can try it specifically if System Repair didn't do the job. At the main Windows Recovery menu, choose Troubleshoot, Advanced options, Command Prompt. A command prompt window appears. Now, you would type a command here: bootrec /fixmbr Type it exactly as shown here, only one space between bootrec and the slash.
You would press Enter and the bootrec program attempts to fix the master boot record or MBR for the Windows boot drive. Now, I'm not doing it here because this PC has no startup issues. If it did, I'd run the program. Generally that would fix it. Close the command prompt window and turn off the PC. When you turn on the system again Windows should load. The operating system is found. If not, the problem may be more severe. For instance, the hard drive could be damaged and need to be replaced.
If you must do so, then you recover Windows, your programs, and all your files thanks to any recent backup you have.
- Diagnosing the causes of PC issues
- Troubleshooting hardware and software
- Performing startup and system restore steps
- Accessing the Task Manager
- Using the Registry Editor
- Fixing Windows
- Maintaining storage drives
- Restoring network connectivity