I'm trying to delete emails before certain date (10/01/2011) from one mailbox. I don't want to adjust any retention policies.
It looks like in Exchange 2007 there was a simple powershell command (Export-Mailbox) to do this, which doesn't exist in 2010. Exchange 2010 has Search-Mailbox (doesn't do dates), and New-MailboxExportRequest.
New-MailboxExportRequest looks like it would do it, but it is unrecognized in Exchange Powershell.