i have restall the window today, but after the installation complete..it appear a msg " and force my computer auto shut down in 50 second everytime i start my comp...is it the cd key problem??? someone please help me.
You have been hit by one of theBlaster worms. This happens when you put an unsecured computer on the Internet to download the patches needed to secure it from the Internet, a neat Catch-22 if ever there was one. The cleanest fix is to reinstall Windows from scratch, then before you go on the Internet, go to another machine and download the following utilities to a floppy from Gibson Research : DCOMbob.exe, ShootTheMessenger.exe, and uPNP.exe. The first one shuts off the DCOM/RPC function that Blaster/Nachi/Welchia uses to infect the system, the second shuts off the Messenger service to prevent spam pop-ups, and the third turns off Universal Plug-and-Play, a security risk. You will still need all the patches from Microsoft, but you won't be infected or have to deal with pop-up spam while you are bringing your install up-to-date.
The other solution is to run a Blaster-cleaner, blow away System Restore, and clean the rest out by hand -- but a reinstall-from-scratch with the Gibson utilities used first to turn off unneeded features is probably better and more reliable.
You will also need a good virus checker. There's a free version of Grisoft AVG and a good firewall, Zone Alarm - free version . See my Malware, virus, and startup information and tools page to protect yourself from scumware.