Check the date and time, if it is not correct, correct it and restart the computer
What is the type of Operating system ? ( Windows XP / Windows VISTA / Windows 7 )
What is the type of internet connection ? ( DSL / Dial-up / Cable / Wireless / Satellite )
Open your mcafee, to the right handside you will see fix, below that it will say "click fix to resolve your issues", below that what does it say ?
Click on about in mcafee, and provide the versions of each and every product of mcafee, Also under virus scan you can see DAT version, also provide that ?
If you are getting any unusual popup, let us know that ?
With all the above details get back to us