Virtual machine is restarting in HyperV in windows server 2008 r2

Hi all,

We have one Windows server 2008 R2 server in which we have one VM having windows server 2003 SP2 and it is restarting continously after some inverval of time. 

What are the things we can check for restarting of this VM.

Thanks & Regards,

Nilesh Kamble