It shouldn't be happening. Do you have Firefox installed? If so read post #3 here: https://community.mcafee.com/message/227496#227496
If not try uninstalling via Control Panel, then running the MCPR cleanup tool listed under Useful Links at the top of this page, reboot and reinstall your product.
Sometimes the installation gets corrupted for various reasons, could be use of registry cleaners, infection, or all kinds of reasons. The above may fix that.
If not then I suggest opening a case with Technical Support, also linked under Useful Links, it's free via phone or online chat.
Do you still get the restart prompts after following the suggestion on the above link , ???