Just wonder do you reboot your computer after updates run? I reboot mine at least once a day and have had no issues such as yours.
You can get another opinion concerning your McAfee installation by running the McAfee Virtual Technician. MVT is found at the top of this page under Useful Links within the Technical Support link. MVT will scan your McAfee software for any issues and will let you know if it it finds any and will attempt to fix them for you.
No, I don't reboot my computer after updates because McAfee doesn't say that it needs to be restarted since the updates were just DAT files for the Anti-Virus.
Not, only that but I noticed that with my Vista computers, sometimes during the Checking for Updates or Downloading Updates step, the Green Bar would change to the Red "Computer at Risk" bar and then in 3 seconds it changes back. This is why I asked if this is a graphical glitch or not, since I have never had the Green Bar change to Red after the updates were done installing.
I have the exact same problem.
I have automatic updates switched on ...but in the past 2 -3 weeks, I'm now getting the exclamation mark saying my computer is at risk.
I run a manual 'check for updates' - it checks, I get a green tick and then seconds later, it's back to the exclamation mark.
If I can be bothered and run manual update over and over again, it eventually goes green.
Please run the McAfee virtual technician . Almost half of the product related issues could be resolved by running MVT from here : http://mvt.mcafee.com
Also, if you have a different security software installed on the PC , it suggested to remove them well in prior before running MVT for better results