I should have added - I'm running 8.7i
I have had this problem a couple of times, different solutions each time...
Heres how I resolved the problem:
1st Incident -
First you will need to remote logon to the virus scan console of the affected PC and disable access protection.
Stop the McAfee McShield service
Rename the file C:\Documents and Settings\All Users\Application Data\McAfee\Common Framework\UpdateHistory.ini to UpdateHistroy.ini.old
Restart the McShield service
2nd Time -
HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\IniFileMapping - If the value of the default key says something like @SYS:DoesNotExist then delete the key...
This fixed the problem the second time I came across is...
3rd time - None of the above methods worked so I determined that the last definition file that was updated was corrupted and prevented the new definition files from downloading (I had this problem when I used to work on symantec products)
Fix for that is as follows:
Assuming that you are doing this all remotely...
First you will need to remote logon to the virus scan console of the affected PC and disable access protection. (From Virus Scan Console - Tools --> Open Remote Console)
Then Stop the McAfee McShield service then Stop the Framework Service on the affected PC.
from a known good machine go the the following location C:\Program Files\Common Files\McAfee\
Copy the Engine folder
now UNC to the same folder on the affected PC (Start --> Run --> \\ComputerName\C$\Program Files\Common Files\McAfee
Delete the engine folder there and paste your new Engine folder into that location.
Restart services, re-enable Access Protection.
On the Remote Virus Scan Console Check the Help About and see if it has updated...
Sorry if all that looks jumbled together... I copied and pasted from my various Troubleshooting Notes...