Creating a routing group connector for Exchange 2010 / 2003 coexistence

Today , I was working at one of our customers site with Exchange migration ( from 2003 to 2010 ) . As part of the installation a routing group connector is need to be created automatically upon the first Exchange 2010 Hub Transport server installation – as below - but for some reason it was not created ! , and hence mail flow between 2003 and 2010 servers was not feasible .

So in order to maintain message routing between Exchange 2003 and the new Exchange 2010 server a routing group connector needs to be in place . I will share here how you can do it , so mail flow is maintained during coexistence .

First of all I ran Get-RoutingGroupConnector via Exchange Management Shell which showed that no connectors were created between Exchange 2003 and Exchange 2010 servers . It can be also checked via Exchange 2003 System Manager .

So I executed the following at Exchange Management Shell ( replace data in italic with yours ):

New-RoutingGroupConnector –Name “Exchange RGC” –SourceTransportServer “Ex10.itguydiaries.net” –TargetTransportServer “Ex03.itguydiaries.net” –Cost 10 –Bidirectional $true –PublicFolderReferralsEnabled $true

Once executed two connectors were created ( bidirectional ) , see below :

You can see it also at Exchange 2003 System Manager

Just as soon as the connectors are in place mail flow between 2003 and 2010 servers worked as it should