We have absolutely no information whatsoever about your PC, so that makes it more difficult straight out of the gate. Is it a custom-built machine or did you buy a brand-named one off the shelf, e.g. Dell, Lenovo, HP, Acer, etc? If so, it might be useful if you have any service tags, serial numbers, or make & model you can share with us.

Can you give us some background details as to when this happened? Did it happen all of a sudden, or was this some machine you've not booted up in a long time? Are you familiar with checking settings in the BIOS?

 

It is a dell and I have been using it all along. When I power it up it says on the screen "Missing Operating System"

 

It is possible that the HDD has gone south. Another possibility is that some Windows files have become corrupt.

With the system being over 11 years old, unless you've replaced the drive at some point in time over the years, I'd be inclined to say the the former is likely the case.

Do you see the drive when you look in the BIOS?

 

According to the service tag and express service code numbers in your image, you have THIS Dell XPS 8300 minitower PC.

According to its assigned support site, it shipped on December 27, 2011 and came with:
Windows 7 Home Premium 64-bit
Seagate Barracuda 500 GB SATA2 hard disk drive

 

...
Seagate Barracuda 500 GB SATA2 hard disk drive

If this is the drive you have in now, then I am impressed it lasted this long and now it may be defective. To confirm if it's a Hard Drive issue, I would recommend either looking at the BIOS screen and under System Information to ensure that the computer sees the drive, or use the Dell Diagnostics to see if it sees it. To get to the BIOS, you would need to press F2 rapidly when you power on the computer until it gets to the BIOS screen. For diagnostics, it will be F12 on boot up, then select diagnostics.

Here is an example of what the BIOS should look like. You should be able to see a Primary Hard Drive section. If it says Empty and you don't have anything else, then the diagnostics should confirm your drive is no longer working.

 

If you have the Win 7 DVD, boot with it and in the second screen click Repair.

 

I did that but it didn't work? Anything else I can do?

 

Yes
Post #7 by James
If you cannot see a drive in the bios = dead drive.
If you can see a drive in the bios you can boot from a linux distro to try and save data

 

Seeing "Missing Operating System" can be unsettling, but it's usually fixable. I had a similar scare once after a power outage. Often, it's due to the boot order or a hiccup in the system.

First, try checking your BIOS or UEFI settings to ensure your hard drive is set as the primary boot device. Sometimes, a loose connection or a failed drive can also cause this issue.

 

Ace, you realize that this thread was from over a year ago, right? While not marked "Solved", the OP has not responded to the last post with an acknowledgement of success, or failure. It is presumed that the matter has either been resolved, or is currently inconsequential.

 

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