How to Seamlessly move a mailbox between recipient containers

Introduction:
Recipient containers are not a practical means to organize mailboxes.  At first glance it may seem like a good idea to an inexperienced Exchange Administrator, but the inherent flaws of organizing mailboxes in this manner, becomes crystal clear when a situation arises that calls for a user mailbox to be moved to a different container.  It is soon realized that Exchange 5.5 provides no means of moving a mailbox from one recipient container to another.  This means the the mailbox must be deleted and recreated in the target recipient container.  Before deleting the original mailbox, the data is extracted or exported using MS Outlook export function, or the Microsoft Exmerge utility.  The last step of the process is importing the data back into the recreated mailbox.

The Problem:
Every Exchange 5.5 mailbox is routed by Exchange, according to it's Exchange Distinguished Name (DN).  An Exchange 5.5 DN is of the following format:

/o=<organization>/ou=<Site>/cn=<recipient container>/cn=<mailbox dir name>

As shown above, the recipient container is part of the Exchange Distinguished Name.  When a mailbox is moved to a new recipient container as outlined in the introduction, there arises a bit of routing problem, when users reply to mail sent from the moved mailbox, while it resided in it's original container.  The problem is the presence of the original recipient container in the distinguished name.  The end result is that any messages, sent prior to the move, replied to, will result in delivery failures.  This typically causes great amounts of confusion though out the user population.

The Solution:
1. Create the new mailbox in the new recipient container, using the same user properties as the original.

2. Log on as the Site Services Account and setup an Outlook profile to access both the original mailbox, and the newly created one, simultaneously.

3. Set the delivery options of the original mailbox to forward to the new one.

4. Remove the smtp address/addresses from the original mailbox and apply to the new one.

5. Hide the original mailbox from the Global Address List

6. Using Outlook, move all messages from the folders in the original mailbox to the new one, preserving the folder tree structure.

7. Remove user permissions from the original mailbox, and instruct the user to create a new Outlook profile, pointing to the newly created mailbox, or to re-point the existing Outlook profile to new mailbox location.   The former method is preferable.

8. Delete the original mailbox after a period of three months or so.

9. Reassign any Public Folder, or other resource permissions over to the new mailbox.

The End Result:
Messages which would have otherwise been non-deliverable, will be seamlessly forwarded to the newly created mailbox, and cause minimum disruption to the user population.