The software only follows what's in the Network Map so that shouldn't be happening unless you have an odd type of connection like VPN, Proxy or similar.
There's no such thing as McAfee Security Plus but there is Security Scan Plus which is not an antivirus. If that is what is listed in Control Panel > Programs and features then you should uninstall it as it is merely a sales tool that downloads with other products such as Adobe Flash, Reader etc. Always check those downloads for unneeded extras.
If it's VirusScan Plus or Antivirus Plus I suggest trying a reboot to see if that helps. (Complete restart). If that doesn't help then I need a lot more details such as operating system and service pack (if applicable), version of Internet Explorer installed (whether or not you use it). Also what security software was installed previously and did you completely uninstall it including the use of its removal tool, probably available on their support pages?