Bit of an issue here, let me explain.

I have had a requirement to change the domain administrator account password for sometime. I have this morning reset the password, to a secure password.

A few months ago I went through the process of checking all the system services, and changing them to another account where administrator was used to run the service. So far, so good.

All has been fine since I changed these accounts, so the password was changed this morning.

Now, we have a situation where we have MS Active directory connector installed to connect an exchange 5.5 server to a 2003 one. Changing the password seems to have broken this replication. Our external outgoing email was routed via the 5.5 box using the ADC, I put the new password into the ADC config tool, but its still broke and I get an error in the event log relating to RPC in the MTA.

An RPC communications error occurred. Unable to bind over RPC. Locality Table (LTAB) index: 3, Windows 2000/MTA error code: 5. Comms error 5, Bind error 0, Remote Server Name exchange5.5servername [MAIN BASE 1 500 %10] (14)

I cant clear this error at all, so now on the 2003 box I have created a new routing group to get the 5.5 server out of the loop completely and all external email is now being correctly processed by the 2003 box, effectivley making the 5.5 server redundant.

I want to now remove the connection between the 5.5 server and the 2003 one, but cannot work out how to go about this, you cannot just remove the exchange 5.5 routing group from the ms exchange 2003 admin tool, it seems to be more involved.

Have you tried installing the 5.5 admin tool (from the 2003 CD) onto the 2003 server and running it from there? You might be able to see and remove the 5.5 objects that way, then remove the ADC (not sure if you need to delete the configuration connection agreement first)?

You have to remove the 5.5 server I think. The Routing Group won't remove if there's a server in it.

I've never done a 5.5 removal, but with 2k and 2k3, it was just a case of migrating everything (public folders, mailboxes, connectors) to the 2k3 box and running the setup on the 2k to uninstall exchnage 2k.

I think I have cracked the server removal, I found a guide on the MS website and followed that which seems to have now deleted the server.

One more small problem, with message delivery. The odd message here and there will suddenly go into the "messages queued for deferred delivery" queue and never leave it. They are all internal messages from domain a to domain a, so I cannot see why they should end up in that queue.

Can the exchange server resolve names in domian B OK wehn the message gets stuck?

I think I have found a fix to the problem, although I am guessing at the cause.

The issue of the stuck messages relates to distribution groups only, from what I have worked out so far.

These groups with problems, were for the most part migrated across from the old exchange 5.5 box 4 years ago although not fully it would seem. For some reason, even though the group has an internal address, exchange message tracking showed that the message was being sent externally and back into exchange hence the message going into a loop.

I have no idea why the Active Directory Connector was not working correctly, and I'll never know since I have now removed it and the exchange 5.5 server from the organisation.

The solution, seems to be using exchange tasks to remove the email address from the affected group(s) and then reapply the email address.

Dont know why its happened, or if it a fix that will work 100% of the time.