XFOR: Microsoft Exchange Server 5.5 Allows Administrators to Disallow Auto Forwarding of Messages to the Internet Addresses

In Exchange Server versions 4.0 and 5.0, administrators can prevent users from sending Out-Of-Office (OOF) messages and AutoReplies to Internet addresses. However, administrators cannot prevent users from auto-forwarding messages to Internet addresses.

In Exchange Server version 5.5, administrators can configure the Exchange Server Internet Mail Service so that auto-forwarded messages are not delivered through the Internet Mail Service.

The Exchange Server Administrator program has two checkboxes for the Internet Mail Service, on a global and per-domain basis, to prevent users from sending AutoReplies and Out-Of-Office messages. If you click to select the Disable AutoReply check box, AutoForwards are also disabled. Previously, auto-forwarded messages were not detected because there were no special message classes or properties on the envelope, as there are for AutoReplies and OOF messages. The Exchange Server 5.5 information store is modified to promote the PR_AUTO_FORWARDED property to the envelope. If this property is present, and the given domain has disabled AutoReplies, the Internet Mail Service discards the Auto Reply message.