Macbook Pro freeze during manual scanning

I have macbook pro 17 inch with Mac Norton Antivirus version 11.1.1 (2)

 

I just bought the NAV less than 1 month, when I tried to do my first manual scanning, my computer always froze almost at the end of the scanning.

 

My harddrive is divided into 2 partitions, one for mac and another one for bootcamp.

 

Please help.

 

 

thank you.