You may receive an error message when you run the Update-SafeList cmdlet in an Exchange 2003 and Exchange 2007 mixed environment

In Microsoft Exchange Server 2007, the safelist aggregation refers to a set of anti-spam functionality that is shared across Microsoft Office Outlook and Exchange. When you add safe senders in Outlook, you must run the Update-SafeList cmdlet on the Exchange 2007-based server to update the safe sender list.

However, in an Exchange 2003 and Exhange 2007 mixed environment, if an Exchange 2003 user sets safe senders in Outlook, you cannot update the safe sender list for this user. For example, you may run the Update-SafeList cmdlet in Exchange Management Shell to update the safe sender list for a user: However, when you do this, you receive the following error message:

To resolve this problem, download and install Update Rollup 5 for Exchange 2007 Service Pack 1. For more information about Update Rollup 5 for Exchange Server 2007 Service Pack 1, see the following Exchange Help topic: For more information about how to obtain the latest Exchange service pack or update rollup, see the following Exchange Help topic:Note Because the safelist aggregation dependency, this hotfix must be installed on the Hub Servers, Edge Servers, and the server on which the Update-SafeList will be run.

For more information, visit the following Microsoft TechNet Web sites: