transport, ex2k unable to email ex5.5 public folders

The configuration and problem is as follows:

Two sites: SiteA is all Ex5.5, with one Ex2k server
acting as SRS, site connector, and ADC target. SiteB is
all Ex2k3 with one Ex2k server acting as SRS, site
connector, and ADC target and one Ex5.5 with no mailboxes
left and about to be decommissioned.

When a user whose mailbox is on an Ex2k or Ex2k3 server
in either site tries to email the SMTP address of a
public folder in SiteA, or even selects the public folder
from the GAL if it has been "unhidden", they receive the
following error:

The following recipient(s) could not be reached:

Postsec - questions on 28/08/2003 10:31 AM
The message was undeliverable because the recipient
specified has changed address permanently and forwarding
was not applicable
<servername.domainname.com #5.1.6>

I did a little troubleshooting and discovered that if you
view the schema properties of public folders replicated
into the Microsoft Exchange System Objects OU by the ADC,
that none of them have the "homeMTA" or "homeMDB"
attribute populated.

So I went to the test lab, which is configured as a
scaled down version of the production environment. In
the test lab if I view the schema properties of public
folders replicated into AD, the "homeMDB" property is
populated, but the "homeMTA" property is not. And there,
users on the Ex2k server in SiteA can email the SMTP
address of a public folder housed on an Ex5.5 server in
SiteA, but users on Ex2k or Ex2k3 in SiteB cannot. I
tried to manually configure the "homeMTA" property in the
schema in the test lab, but even with that field
configured the error still occurs when sending from
SiteB. I might not be configuring it properly, but I
assumed it would be similar to the same attribute on
mailboxes. A trace on the message in the test lab shows
it is getting all the way to the Ex5.5 public folder
server, which is the server that is generating the NDR
and sending it back.

I have a temporary work around in that if I configure the
public folder to be the only recipient of a distribution
list, set the "Expansion Server" of the distribution list
to an Ex5.5 server in SiteA, and select to hide the
distribution list membership from the global, mail will
be delivered.

However, since we will be running in mixed mode for at
least several months, I am looking for a solution rather
than a work-around.

Thanks.

For mail flow to work as expected to a PF in a mixed mode environment, you
will need to configure a Public Folder ADC Connection Agreement.

If that is not an option for you, you should the PF to the Exchange
2000/2003 servers.

Doug Blanchard
Microsoft PSS

Please do not send email directly to this alias. This alias is for newsgroup
purposes only. This posting is provided "AS IS" with no warranties, and
confers no rights.

have already put a Public Folder CA in place, thats how
the public folders got into the AD.

And unfortunately at this time I do not have hardware to
house Exchange 2000 and all the public folders. That is
coming but it is several months away, and in the interim
the Ex2k users need to be able to email the public
folders.

mode environment, you
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