Computer will not bootup

HP Pavillion a744x

RUnning Windows XP

When starting the computer it goes to a black screen. It says We apologize for the inconvenience, but Windows did not start successfully. A recent hardware or software change might have caused this.

If your computer stopped responding, restarted unexpectedly, or was automatically shut down to protect your files, choose Last Known Good Configuration to revert to the most recent settings that worked
If a previous startup attemt was interrupted due to a power failure or because the power or reset buttom was pressed, or if you aren't sure what caused the problem ,choose Start Windows Normally.
Safe Mode
safe Mode with Networking
Safe Mode With Command Prompt

Last Known Good Configuration (you most recent setting that worked)
Start Windows Normally
Use the up and arrow key to move te highlight to choice



If I choose start Windows Noemally It count down from 26 to 0 show windows xp logo go to Hp logo then back to the black screen