It could be that that McAfee is detecting (AVG) as a security application, which is incompatible. You of course can try to (Exclude) this application and see if that resolves your issue.
Dell Tune-Up Utilties is more than meets the eye. Some call it bloatware. I know that was the first thing I got rid of on my Alienware machine. That "Optimize" is a euphemism for Registry Cleanup and McAfee reacts badly to such things as they can be quite dangerous for any system as in the end they invariably remove more than they should and you end up with a malfunctioning system.
Windows has it's own Disk Cleanup utility which is far more trustworthy and wont remove bits of software you need..
You could open a case with Technical Support I suppose but they will tell you more-or-less the same thing.
Moved to Consumer >General > Discussions
I have to concur with Colleage Ex_Brit as his analogy is indeed correct. I also advise/discourage the use of Registry Cleaners/Optimizers as general a whole. For eventually they can do more harm, than good.
All the Best,
Thank you for your advice and support.