I don't want currently update to ePO 4.0 or 4.5, because we are looking for another antivirus solution this year. VirusScan slows down our clients very much (we have over 800 software developer which are very heavy power users (Quadcore core i7, 12GB Ram, two 500GB HDD for local two channel compiling). I have added a lot of file extensions and paths to exclude the scan process. Unfortunately the more I added these exclusion the more VirusScan slows down. Even in 8.0i, 8.5 and 8.7 Sp2. We notice a general performance issue with VSE 8.7i Sp2 on Windows Server 2003 Sp2 with installed Apache server. 8.7i slows down the bandwith of HTTP traffic very much, even if the complete VirusScan is disabled (Bufferoverflow, ScriptScanning, OnAccessScan). Sysinternals Processmonitor capture over 40% kernel time if VSE 8.7i is installed. So it looks like a kernel driver problem with VSE (please notice with VSE 8.0i the kernel time is only between 10% and 30%!)
We made currently a field test with Avira AntiVir it looks that the performance problems goes away. btw. Any user which had switch from Avira to McAfee ? :-)
Just ran into this problem this week. McAfee Tech support told me that you won't be able to manage or deploy to Windows 7 systems from EPO 3.6.1. The reason is that they have not created a NAP file that will allow it to work. This happens with the latest MA 4.0P3. They told me that we have to upgrade our server to either EPO 4.0 or 4.5.
I first noticed the problem when I couldn't manage Windows 7 RTM from my virtual test EPO 3.6.1 server. It worked after the server was upgraded to EPO 4.0.
We are now going to upgrade our production EPO 3.6.1 server to EPO 4.0 this weekend. This upgrade is a lot sooner than I wanted but it has to be done since EPO 3.6.1 End-of-life is fast approaching (Dec 31st 2009).
We also won't switch EPO 4.5 until either the first or second patch is released and the product becomes more stable.