Win 7 updated from Vista: Came home to find Mcafee had auto pushed Security Center 10.5 and asked me to re-boot system. 9.5 had been working OK. Once re-boot had finished, Mcafee would not open and told me that I had 'no active anti-virus security.' Went to Mcafee 'chat support-remote control ' where I had to pay $59.95 BEFORE they would even begin answering any questions. A very, very long story short here...after 6 hours and 2 Mcafee technicians, they were unable to fix whatever the issue was. In the end, the second tech stated that they would call back in two days (a time was set) as they had to look into the problem. Two days later, they did call back. I told the Mcafee tech that I wanted to absolutely clear out EVERY Mcafee file on my computer (watching the screen over the two days there must have been hundreds of Mcafee files spread out all over the computer) as I was moving to another security program because of what just happened and the fact that the price for re-newing the license in my opinion was outrageous. Three hours later on the second day, Mcafee finally succeeded in deleting all/most of their files from my computer. This tech mentioned something to the affect that going to 10.5 from 9.5 on a windows 7 computer that had been upgraded to Windows 7 from Vista was a known problem. Gee, wouldn't you think that the Mcafee installer would recognize this install issue and NOT try the install? After complaining to customer service, they refunded my money and it showd up on my CC a few days later.
I installed Microsoft Security Essentials (free + good rating from PC World), turned on the MS Firewall (passed the GRC Shields UP https://www.grc.com/x/ne.dll?bh0bkyd2) and installed Malwarebytes (free, but I upgraded to full version for $21, unbelievably less than what Mcafee wanted for a 2 yr license) All works well together. I have also noted in 'task manager' a reduction in the # of tasks running and lower memory usage. This decision has been a no brainer for me.
In fairness to Mcafee, I had had their software pre-installed on my computer for nearly 3 yrs and although from time to time I had had some issues, I was pretty much happy with it. After this debacle, I am out-of-here. Hope this information helps someone else, certainly cause for concern if your computer situation mentioned above is similar to mine.