Disk Boot Failure

Im running Windows XP on my home computer. When I start it up, on the black screen it says at the bottom "Disk Boot Failure Insert CD and hit enter." I do not have a boot CD... and inserting the XP CD does nothing for me. It has 1.6 GHz, 990MHz, 512 MB of RAM. I had this problem before and took it somewhere, it was fixed but the guy didnt tell me what was wrong with it, and I refuse to spend another $150 on it... can you help me please?

 

Go into your BIOS and change the boot device priority. Make sure your HDD is number 1 (at the top). To access your BIOS press the DEL or F2 key at startup.

 

Thank you for your quick response... I tried what you suggested. Here is the exact error messages: "Unknown Flash Type DISK BOOT FAILURE, INSERT SYSTEM DISK AND PRESS ENTER" ...any advice?

 

Go into your BIOS and load the optimized defaults, save, exit and reboot.

Or, get a boot CD with HDD diagnostics on. It is most likely a HDD problem.

 

I loaded the optimized defaults... theres a new error message now, similar but different... it says "Boot from CD: Boot from CD: DISK BOOT FAILURE INSERT SYSTEM DISK AND PRESS ENTER" ... thank you for trying to help, I'll try getting a boot CD, like you suggested. Thanks again