The best way? Upgrade to a supported version of Exchange that has that cmdlet.
Otherwise, it depends on your scripting ability. You might be able to do this by writing a PowerShell script that iterates through all mailboxes and rules and collects a list. If that's too complicated for you to do, or too expensive for someone
else to do, then maybe the best way is for you to log on to each mailbox and list and record the rules.
Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."
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