XP forcefully restarts in safe mode

hi
i am using xpsp2 from last couple of days when i start pc itboot in safe mode but not in normal mode why is this happening? t restart again and again but it not starting in normal way. please tell me how can i fix it. thank you.

there must be some problem regarding application so in safe mode run scan disk.uninstalled all unnecessary application mostly ,most recent application that you had installed. and reboot hope this will work.

this can be hardware problem also if you install any new devise uninstall it,or also check for new driver that you have install due to which their may conflict so uninstall new drivers that you installed.check for hard disk bad sector also.