Kasper internet security has slowed down pc

Hello,
I have Kaspersky internet security installed in my PC and it has slowed down the PC.
I need to know why is this problem happening.
So far I have known there are other people using this internet security but they do not seem to have this problem.
If it is a problem with the settings then I really need to know how to fix it.
Please someone enlighten me on this problem.
Benjamin Morgan
