3. Launch Windows Explorer and delete all McAfee files in "Program Files" but especially in "C:\Document and Settings\<user>\Application Data" and "C:\Document and Settings\All Users\Application Data". You have to set Windows Explorer to show all hidden files and folders (Tools > Folder Options > View tab). Just delete the McAfee folders even if they are empty in all the "Application Data" folders. Can be more than one! In Vista: C:\Program Files, C:\ProgramData and C:\Users\yourname\AppData\Roaming If you can't find these files don't worry. It just means that MCPR has done its job.
4. Reboot and re-download/reinstall your McAfee products directly from your account at the McAfee web site.
The installation will automatically disable Windows Firewall again and, if you are using Vista or Windows 7, disable Windows Defender. You can re-enable Defender if you wish.
Repeating the same post when asked for more information does not assist us in helping you.
What Peter asked for is have you an account that you can download mcafee from? ie did you buy it or is it through Dell or another partner etc?
If you can verify that you have an account run the mcpr Removal tool (from my and Peter's signature) to ensure the clean removal of all bits of the old program. Reboot then reinstall from your account.