When you uninstalled Norton did you also run their removal tool?
There is another thread on exactly the same issue and the advice in this post may be helpful: https://community.mcafee.com/message/314005#314005
Please try my suggestion on the other thread Peter posted and check if that helps..!
The McUICnt.exe will not load whenever McAfee has installed updates and Requires Restart for completion of Update Installation. Try the below steps and post the Outcome..!
Open McAfee UI > Update Tile > Update Settings > Choose option "Download Update and do not Install" > Click Apply and close McAfee User Interface.
Try updating McAfee manually and wait for it to download and Install. Restart the Computer and check if the Update Settings are set to Download and Not Install.
After this McUICnt.exe should not Interrupt the Media Extender.
I did the "Download Update and do not Install" and restarted my PC. WMC on XBOX still disconnects after 2 minutes.
Message in the MediaCenter error log is The Media Center Extender session was terminated because an unauthorized window opened in the session.
I ve had one such case in support where the issue gets resolved by turning Off "Access Protection". However I would not recommend having it turned OFF. The issue was reproducible where AP disconnected the Media Extender in 2-3minutes.
Everyone whom facing the same issue Please call Tech Support and open a Service Request. This will be helpful for collecting information required to progress in this issue.
Action: logs are to be collected from machines with this issue and needs to be updated to higher level team for further proceedings. Please note that the Severity of this Issue will considered based on the number of Service Requests we receive and not by number of threads/posts here and elsewhere.
none of the options suggested works for me.
yesterday I turned off FireWall for 15 minute and the Extender continued to work flawlessly even after the Fierwall turned on after 15 minuts. this morning had the same issue again when the computer wokeup from sleep.