"Operating System Not Found"

[The Thrashmeister]

For the past two weeks or so, whenever I turn on my computer, it never starts up on the first try. It always beeps twice and shows this black screen with white computer-style text on it, some crap about BIOS? It says press F1 (or was it F10? can't remember) to "Resume," but when I do that, it goes to another black screen that says "Operating System Not Found." But whenever I just turn the computer off and on again, it starts without any problem and I can go about my business as per usual.

However, this is starting to worry me as just a few minutes ago, I increased the paging file size on my computer and turned it off to make the changes take effect. The same black screen thing happened again, except this time, it happened three times. Only after I turned my computer on again on the fourth time did it start normally.

I'm not really that adept with computers so I'm not entirely sure what's happening. Superficially, this doesn't seem to be harmful, but I don't know, it might get worse in the future. Can anyone explain why this keeps happening, and how I might fix it?

I also have a more minor problem concerning Mozilla Firefox. I have the latest version, whatever version number it is, and no matter what I do, I can't seem to clear my browsing history. I set Firefox so that it's supposed to clear private data everytime I close it, but it seems to be closing everything BUT the browsing history. I tried the same thing on my parents' desktop, and the browsing history cleared just fine. Any help with that too?

 

[Pokemon_Veteran]

Why exactly did you change your pagefile size. A pagefile size should be increased only if you have not enough memory, since a pagefile acts like RAM.

Well, can you give me more details on how old your computer is or what os(XP, Vista, MAC) you are using. I need more details since many things can cause that to happen, like malware, age, failure, or filesystem corruption.

 

[The Thrashmeister]

Why exactly did you change your pagefile size. A pagefile size should be increased only if you have not enough memory, since a pagefile acts like RAM.

I was researching ways to increase my computer's speed. Again, I don't know that much about computers.

Well, can you give me more details on how old your computer is or what os(XP, Vista, MAC) you are using. I need more details since many things can cause that to happen, like malware, age, failure, or filesystem corruption.

It's running Vista. Got it on Christmas of 2007. Not sure what else could help...

 

[Pokemon_Veteran]

Okay, a hard drive normally doesn't fail after about 2 years, so I don't think the hard drive is failing.
One thing I can safely say is, back up your important files like photos to an external storage device or a cd/dvd or create a recovery partition, that is always a good idea especially if your computer is doing this.

Personally, I myself would back up all my files, wipe the system partition, and reinstall windows which is certain to kill any virus on the computer and fix any filesystem corruption. If it doesn't fix the problem, it is a hardware failure of some sort.

Would you want me to help you create a recovery partition?