You should try to run the McAfee Virtual Technician found at the top of this page under Useful Links. MVT will scan your computer for any McAfee issues and attempt to fix them. It will generate a session id which you should post here for the moderator to review. If MVT finds something it cannot fix then I suggest you contact Technical Support Chat also under Useful Links for diagnosis of your issue(s)
You mentioned you have uninstalled your software. Have you used the MCPR removal tool? You may have some corrupt files that Add/Remove failed to get completely out.
It might also be helpful to know if you are up to date with Microsoft updates, what operating system you have, how much ram,etc.
If your issue is in conjunction with the 5958 problem you need to follow up with McAfee. That is why I recommend contacting Chat.