I just upgraded everyone to VirusScan 8.7 using ePO4.
The result was Scanotlk.dll could not be installed ot loaded.
This was not what I wanted to see when I did the upgrade.
So a friend M. Jacquard (CISSP and a great guy to boot!) gave me a fix...

The problem is:
Outlook caches registry info on plug-ins in a file named extend.dat.
The path was changed in 8.5 to "C:\Program Files\McAfee\VirusScan Enterprise\Scanotlk.dll" and extend.dat is out of sync with the registry settings.
You can delete extend.dat and Outlook will recreate it the next time it starts.
I just added this to our GPO login script for the duration of our roll-out:

----------Copy the text below into a bat file----------
C:
cd %UserProfile%\LocalS~1\Applic~1\Micros~1\Outlook\
del extend.dat
exit

----------Copy the text above into a bat file----------

MAKE SURE NO WORD WRAP IS HAPPENING IN YOUR SCRIPT
USE AT YOUR OWN RISK!

1. Run in a logon script or add to a GPO.

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