İ would first ask DELL whether McAfee is embedded in the system,(send them a formal request,NOT just any rep on the phone)and if it can be removed,ask them how to!
İf their suggestions don't help, try uninstalling McAfee using REVO in Safe Mode.
Then while still in Safe Mode,search for and delete any folders of McAfee you find in Program Files.
İ would then go into the Registry Editor ( but ONLY
if you're comfortable and familiar with it)and remove any entries of McAfee there as well.
You could also try to disable it,uncheck any Startup entries of it,then try and delete it as suggested above.
P.S Have you checked your user manual for any entries regarding McAfee?
Edited by Julia G, 11 November 2012 - 08:13 AM.