Not that it is that but my kid's machine did the same. I unplugged the USB scanner and it continued to boot. I've seen that effect on other USB devices so power down, unplug all USB things (even the keyboard, mouse) and try one more time.
Bob
Hi, all, this is what just happened to me. The system have asked me to update the window and so I did, after that, everytime I log into msn messenger, my computer freezes, I've had a system restored after but the msn messenger still freezes my computer and I could do nothing except for turning off the power supply. After turning back on the computer, it couldn't start. I mean, the computer does turned on with one beep as always and the fan and the led light are all working but when it goes onto the screen where it has a big dell and F2 F12 option, it stopped moving onto POST. I've tried to press F2 F12 F8 Del and every buttons on my keyboard but nothing happened after that.I've also remove my rams, cleaned the **** and put them back on but still didn't work. Used my spare keyboard and mouse, and still...
My computer is a Vostro 200 with XP SP2 that I bought about 1 and half years ago with 4 Gb kingston ram that I upgraded 6 months ago. I am wondering if anyone know what is causing this problem. I hope its not the motherboard.
Thanks!!

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