I've been having this problem for a few weeks now. It seems to have gotten worse following the removal of the NTOSKRNL-HOOK infection and its pesky friends.
Pre-infection I was having issues running both manual and automatic scans, getting the above error. After several tries manually it would eventually scan. Now, post-infection removal I cannot get viruscan to run at all, receiving the above error.
I have scanned with Malwarebytes, Super AntiSpyware, and found no lingering infections.
I downloaded and have run the McAfee virtual technician several times and keep winding up with the same problem... DAT not up to date, Expected 5738, Existing 5735. I let the technician do its fix, try scanning, and it does not work. I go back to the technician and it gives me the same DAT out of date message.
Are there additional steps I can take here or do I need to wipeout McAfee and start from scratch? Thanks