If you are experiencing troubles with McAfee such as update or scan issues and wants to know that how to fix McAfee Antivirus is using 100 CPU and memory so first of all you need to know that this software has multiple documented use cases and in many causes the program to take over the CPU of the computer. McAfee Tech Support process uses the McShield.exe program to provide the service.  Mcshield.exe provides real-time scanning for the McAfee Antivirus program, scrutinizing the files the user accesses. While, this process does not automatically remove a malicious file, when it finds one, it does alert the end user, allowing him/her to decide what they would like to do with the file. It is designed as such to protect the computer from the malwares and spywares and remove the existing infections. To fix McAfee 100 CPU usage problem and you can get in touch with McAfee Tech Support for call assistance on toll free number 1-800-890-9109 and get fix the issue easily, the technical team will always being ready to help you, so just call them and get fix the issue as soon as possible.