If you do not uninstall McAfee before installing a newer or another product version, it will create software conflicts and slow down the computer. You may also encounter windows crashing and sluggish behavior. Hence, you need to follow the correct procedure on how to uninstall McAfee from your PC.

Steps to Uninstall McAfee computer:

• Click on “Start” and open “Control Panel”
• Click Programs option in the Control Panel
• The option may vary as per your Windows OS version
• On the next page, click Programs and Features
• Select un install a program
• From the program directory, click-right on ” McAfee” icon
• Click on Uninstall/ Change option
• Click the “Yes” if asked -“Are you sure, you want to completely remove McAfee, and proceed
• Restart your computer

See McAfee window opening up when you turn on the computer, the software is not completely uninstalled yet and may need a virtual technician for complete un-installation

Web-source : https://www.mcafeetechnicalsupportnumber.com/uninstall-mcafee-antivirus-from-mac