Have you checked your hard drive for disk read errors? Try running a chkdsk /r (the /r parameter detects and tries to repair errors). Sorry, without knowing your operating syste,/service pack I can't offer advice on the best way of doing that. The only other reason I can think of would be a corrupted file - is the McAfee software, whatever it is, behaving as it should?
Sorry if I'm using this incorrectly. I checked to see if there were any disc errors and there weren't any errors. Also I again tried to defrag the computer and it got stuck at 62% again. when I tried something else the computer froze and I had to manually push the power button to turn it off.
The computer is a Lenovo, approximately 1 year old as of September. The operating system is windows 7.
Make sure your Windows 7 is SP1 and totally up to date and, regardless of what browser you prefer to use, also make sure that IE11 is installed. Even if you use another browser, McAfee relies on IE for functionality.
Then I suggest you open a case with Technical Support. It's free of charge by phone or online chat and linked under Useful Links at the top of this page.
Before connecting the website will ask you to run the Virtual Technician. often it can find and fix issues by itself. But if not simply continue as instructed and link up with support.