I'm not familiar with Mcafee products but will try to help until someone else who is comes along.
Is your Mcafee anti virus a separate program on a CD that your trying to reinstall, Or is it part of AOL's software?
When you say "Back on line" do you mean you have managed to install it but not able to configure it to keep your system safe?
Are you using XP with SP2? Please post back with this info and I will see what help I can offer. If unable to help it is information that is needed for others to help.