If there exists a remnant file from the previous uninstall , this could happen . Please run the McAfee removal tool from here : http://download.mcafee.com/products/licensed/cust_support_patches/MCPR.exe.
Restart the computer
Run the Mcpreinstall tool from here http://download.mcafee.com/products/licensed/cust_support_patches/McPreInstall.e xe
Login to your McAfee account and reinstall your McAfee programs
That would be normal if there was a major change in the software.