Question : Sending E-mail from Exchange 2003 Public Folder through 2007 CAS

We have a Mixed Exchange 2003 and Exchange 2007 Environment while working on this transition. Currently the 2007 CAS is in place, directing mail, but the Mailbox server has not been made live (it is however operational). Sending to old public folders is fine, however we had to create a new mail-enabled public folder on the 2003 system. When attempting to send an E-mail to it through the new 2007 CAS we receive the following error:

550 5.2.0 STOREDRV.Deliver: The Microsoft Exchange Information Store service reported an error. The following information should help identify the cause of this error: "MapiExceptionNotFound:16.18969:9B000000, 17.27161:0000000074000000000000000000000000000000, 255.23226:666F3A20, 255.27962:44000000, 255.17082:BFF9FFFF, 0.25697:02400080, 4.21921:BFF9FFFF, 255.27962:FA000000, 255.1494:02400080, 255.26426:96000000, 4.9206:BFF9FFFF, 4.7974:BFF9FFFF, 5.10786:0000000045584348414E474532004348414E4745, 255.1750:32333A35, 0.26849:3A383734, 255.21817:BFF9FFFF".

If I manually telnet to the SMTP of the old 2003 Front-End, I can send E-mail to the public folder with no problem. I have tried turning on public folder replicas for that folder, deleting and recreating it, even setting up a distribution group to route to the public folder in hopes that I could trick it into working to no avail. Any ideas would be helpful as I have reached my wits end.

Answer : Sending E-mail from Exchange 2003 Public Folder through 2007 CAS

Had a similar problem and the solution was to replicate the pub folder to the Ex2007 server and after replication mail was delivered no prob... not sure if this will help you....?!