[Problems running] defrag

on my dell lat 366xt laptop I can not run defrag........it has gone as far as 19 min but thats it........programs are shut down and no one has touched the computer while running.......continues to go back to 0% any ideas? thanks

 

Have you tried running it in Safe Mode? To enter Safe Mode, repeatedly press and release the F8 key while the computer is booting. That should get you to the boot menu where you can choose Safe Mode.

 

If a process writes to the drive while it's being defragged, defrag will start all over.
It could be an application logging, windows event log, an autoupdater, or just about anything writing to the drive.
Check your event logs for new or recent events, they may help find problems you didn't know your PC was suffering from.

Defrag is best done in safe mode, or using a 3rd party command-line pre- Windows logon type program.