My McAfee's antivirus goes offline a lot. Not all of the time but a lot. I turn it back on and then I will notice that it is offline again when I get a pop up indicating that my computer is unprotected. I scanned the computer with McAfee after bringing it back online and nothing was found. Generally, I run Combofix but it seems to be off line now. I asuume that this is a virus but nothing shows up.