So here is the issue i have had, and hopefully there is something someone knows to help me. For years I have used an old version of Antivirus, i am talking 2003 at best and it worked fine. My desktop is running Windows XP professional. Recently I got a new hard drive, reloaded the system and upgraded to Norton Antivirus 2009. After installing it, Antivirus runs it Live Update then requires a system reboot, so I allow it and then it gets as far as the Windows splash screen and then it goes blank, screen is black, the "busy" light on the computer itself doesnt even flicker. No matter what I do it wont boot up. I have to go into safe mode to remove Antivirus, then the system boots perfectly. I tried with a copy of Norton Antivirus 2010 also and the same results. They are legal, sealed when i bought them copies, and its a legal sealed copy of Windows XP. What am I doing wrong here? My laptop with Norton Anti Virus 2010 and Windows 7 works perfectly, I just need my desktop to work now.