I had been doing a lot of web surfing that day. That evening I noticed the computer freeze-up when it went into screen saver mode. The HDD would make a series of clicks and then pause. This would go on and on requiring a hard reboot to stop it. This same computer freeze with an endless cycle of HDD clicks and pauses would occur anytime I entered screensaver mode, or ran any disk checking utility such as defrag, Norton disk doctor, Norton antivirus. The computer would freeze at the same location when performing antivitus or disk doctor. I found the file that caused the problem. It was one jpg file from my digital camera that I had downloaded 10 months ago. Everytime the computer came across this file the computer would freeze. Otherwise the computer worked fine. I tried everything to delete it but without success. I even tried to reformat the HDD (WinXP Pro) and the computer again froze up with the clicks and pause cycle occuring during reformat. I finally used an IBM disk utility that told me that a sector was damaged and then asked me if I would like to repair it. I repaired it. After this I was able to reformat the HDD and reinstall WinXP Pro. It's been 3 days now and the computer works flawlessly. My question: Was that a virus (Norton AV did not detect it) or is my HDD about to go bad (Do I need to replace the HDD)?