How to fix a computer that won't start

A computer that won't start is frustrating, but the problem is often easy to fix. The steps you take to troubleshoot the problem depend on your symptoms. Because different problems require different troubleshooting steps, it’s not necessary to read all of these instructions. Instead, click on the link that best describes your problem: •You log on by clicking your user account, but then you can't open any programs. •Your computer displays the Windows logo, but fails before you can log on. •You see "Non-system disk or disk error," or a similar message. •Your computer stops immediately after you turn it on or displays nothing on your monitor. •Your computer does not turn on. •You need to perform a repair installation of Microsoft Windows XP.