When I switch on my mobile phone dopod C730, it

When I switch on my mobile phone dopod C730, it continuously reboots after the screen Windows mobile appears .
It means that I cannot have the main screen on and cannot give any phone call or access the information that is on my mobile phone.

Is there any way I can reset the phone except by taking out the battery. If I take out the battery, then put it back and switch on the phone, it reboots continuously.