I am running Anti Virus Plus (been using it for a LONG time) on Window 7 (I've had this laptop for 3 year). I use Eudora for my email client. Until this last update, I had no problems when the real time scanning was enabled. Now I have to turn it off if I want Eudora to finish downloading my email. If I don't the mcshield.exe process eats up between 75% and 100% of the cpus (4). Since Eudora is a mature product and hasn't been updated in years, this can't be blamed on a version of Eudora. I saw other complaining of a similar problem when using Thunderbird, so it looks like a problem with McAfee. I will turn off real time scanning for now, but that is NOT a solution.
On a side note, the new interface is lousy & takes up too much space for the amount of information that is displayed.
Re interface I assume you are using it on 1024 by 768? That is its lowest resolution and better on higher resolutions. We mods have mentioned this in our calls but no answer as yet. I would assume they (the developers ) have their reasons but a sizing option would be handy.
Re eudora you need as I mentioned to the thunderbid poster to call support and log a call. Only way they will know there is an issue.