as per Microsoft "When you install Exchange2010 into an existing Exchange2003 organization and perform journaling in this mixed organization, we recommend that you configure all distribution groups to use Exchange2007 Hub Transport servers as distribution group expansion servers. This is recommended because messages would not bejournaled, even if the recipients are configured for journaling, if the following conditions are true" How do you move/migrate all DL to only use hub transport servers? from what I can see you only have the option to chose "any server in the organization" or hard code to a single Exchange 2007 server, i.e. single point of failure. Can I tell my Exchange 2003 servers to never expand distribution lists so that all the Exchange 2007 systems take care of this? My concern here is making a single E2K7 server a single point of failure for DL expansion so what I need is for DLs to be expanded ONLY on ANY Exchange 2007 system in a mixed E2K3/E2K7 environment. Can I do this? Thanks

First of all you need to use Exchange 2007 article instead of Exchange 2010, however there isn't any difference in both article in this mixed mode journaling regards but there might be if you are checking for any other subject on Exchange 2007... :) Understanding Journaling in a Mixed Exchange 2003 and Exchange 2007 Environment http://technet.microsoft.com/en-us/library/aa997918.aspx Ok, back to business. The sentence you mentioned is applies to the DLs which are set with specific Exchange 2003 server in Exchange Advance tab. If it is set with "Any server in the organization", which is by default set when you create new DL, then it is fine and no need to set specific Exchange 2007 hub transport server there because when somebody sends an email to tht DLs, first Hub transport server will pickup and journal the mail as per Journaling Rule. Check below example for further understanding which is given in same article... -==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==- For example, assume that the Sales distribution group includes Exchange2007recipients and that it is configured to useanExchange2003 distribution list expansion server. In this case, whenanExchange2007 sender sends a message to the Sales distribution group, the following events occur: The message is sent to a Hub Transport server. Because the Sales distribution group is not configured to use a Hub Transport server as the distribution group expansion server, the journal rules in the Exchange2007 organization cannotaccess the distribution group recipients. Therefore, no journal rules can be applied to the recipients in the distribution group. The message is routed to the Exchange2003 server for expansion. The Exchange2003 server expands the distribution group. Because the Exchange2003 server cannot access the Exchange2007 journal rule configuration, no messages are journaled. The Exchange2003 server routes the expanded messages back to the Exchange2007 Hub Transport server for delivery to the Exchange2007 recipients. The Hub Transport receives the message. Because this is not the first server to route these messages, the Hub Transport server assumes the messages have already been evaluated for journaling and the journal rules are not applied. -==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-Amit Tank | MVP Exchange Server | MCITP: EMA | MCSA: M | http://ExchangeShare.WordPress.com