You need to finde out which file is slowing it down so much, maybe archive or something, or just remove docs to other destination for example in local disk d and see how that affects.
No solution for you---I had the same problem last week. Used the CHAT facility and was told I had an infection which turned out to be untrue. It was jusdt a way for the operator to terminate the session I think.
Unintalled and reinstalled. Still have the same issue today and CHAT not responding.
RAM useage is 100% and the machine will not respond the CTRL ALT DEL---I can hear it going to disk every 15 seconds and nothing works effectively.
I have reached the end of my tether with this product and not about to spend my time diagnosing it for them.
I would do as I am about to do.
Remove Mc Afee and replace it with the free Microsoft essentials product. Has no noticeable impact on performance and in my case( I tried it last week before I thought I'd give McAfee one last try) it found issues that were mised by McAfee.
Now I have a job since I run 9 licenses for this product that I will have to spend time undoing. I really didn't need this at this time of year.
Best of luck with your choice try
http://www.choice.com.au/reviews-and-tests/technology/software-and-online-servic es/security/security-suites-review-and-compare.aspx and you'll see that McAfee is very much an 'also ran' product---I only persisted with it since I had so many licenses and it was what I would term 'adequate'