network problem

The network has had a problem and it may be caused by Sophos Anti-Virus software, it was using 57,688K of mem usage.

This is because it may have been updating and because there are many PC's on the network all updating at the same time it slows down the network and causes certain PC's to freeze and become none responsive, ive had this problem 3 times and had to restart the machine 3 times.

above the sophos screen

to the left task manager