Email delivery problems with Exchange 2003/2007, McAfee GroupShield 7.x and McAfee VirusScan Enterprise 8.x

We recently come across several instances of an issue where email delivery is delayed on an Exchange server - mail flow can sometimes be quick but is often slow and messages are delayed by minutes or hours. In a couple of instances this was traced back to the fact that these servers were all running McAfee GroupShield 7.x and McAfee VirusScan Enterprise 8.x. It seems that somehow (either via an update or the original installation) the exclusion path for Exchange seems to have a malformed path. To fix this, go to the VirusScan Console > On Access Scanner > All Processes > Detection > Exclusions. Highlight the mailroot path and edit it to remove the double backslash from the path. Also check that the other relevant exclusions from https://kc.mcafee.com/corporate/index?page=content&id=KB55595 are in place.

Microsoft PSS seem to recommend that you exclude the entire inetpub directory and all sub-directories from scanning.