Computer shuts down constantly and so frequently - System config Windows Vista, Norton 360 V4

I have 360  version 4.0 for 2 computers. No issue in Windows XP and in Vista. However for the last weekonwards the Windows Vista computer is shutting down like maniac allowing me to do nothing. I am not even able to uninstall it and the computer shuts down. Then it goes to windows repair mode and even that does not complete.

 

System Config:

Toshiba Laptop

Windows Vista

Norton 360 V4 installed Jan 2011

 

Details of problem:

Computer shuts down very frequently.

Frequency is less than 10 secs to sometimes upto 3 mins.

 

Symptoms:

360 shows computer not protected due to Sonar protection error.

 

Tried:

To download uninstallation info from Norton - System drops dead before it can be completed.

Tried to start in Safe mode system shuts down

WIndows tries to repair - Repair not compete.

 

Well every time the computer attempts to start, it gets to the Windows screen where you click on the user to sign on, then it starts up for about a minute then just shuts down.

 

But I can't keep the computer running long enough to do anything else with it, even in the safe mode.  Anyone else hear of this?

 

I have 360  version 4.0 for 2 computers. No issue in Windows XP and in Vista. However for the last weekonwards the Windows Vista computer is shutting down like maniac allowing me to do nothing. I am not even able to uninstall it and the computer shuts down. Then it goes to windows repair mode and even that does not complete.

 

System Config:

Toshiba Laptop

Windows Vista

Norton 360 V4 installed Jan 2011

 

Details of problem:

Computer shuts down very frequently.

Frequency is less than 10 secs to sometimes upto 3 mins.

 

Symptoms:

360 shows computer not protected due to Sonar protection error.

 

Tried:

To download uninstallation info from Norton - System drops dead before it can be completed.

Tried to start in Safe mode system shuts down

WIndows tries to repair - Repair not compete.

 

Well every time the computer attempts to start, it gets to the Windows screen where you click on the user to sign on, then it starts up for about a minute then just shuts down.

 

But I can't keep the computer running long enough to do anything else with it, even in the safe mode.  Anyone else hear of this?