What has changed?
When your mailbox moves to Office 365, you will need to be aware of 2 major changes from what you are used to.
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What happens right when my McCombs mailbox moves to Office 365?
Your mailbox will move in the background, so you do not need to do anything to prepare for it and you should not notice anything happening while your mailbox is being moved. Once the final step of the move completes your mailbox will no longer exist on a McCombs email server, and you will see one of two responses in your email client depending on which client you use.
Outlook on Windows and Mac
If you are logged in using Outlook on Windows or Mac you will receive a message that a change has occurred with your mailbox and you need to restart Outlook. Just restart Outlook. The application should automatically configure itself to work with your new Office 365 mailbox. Everything should look exactly as before. If you were logged off at the time that your mailbox move completed, then when you launch Outlook for the first time after that you will notice it takes a couple of minutes to reconfigure itself, but afterward everything should look exactly as before.
MacMail, iPhone, iPad and Android apps
In almost every situation, any client other than Outlook will simply inform you that it can no longer connect to your mailbox. In only a few cases have we seen a non-Outlook client reconfigure itself simply by restarting it. In all other cases, you should expect to have to manually remove your old email profile and create a new one. Please see below for more information on how to configure various email clients.
Special note about multiple logon prompts
Regardless of which email client you use, if you have connections to shared folders or calendars in other mailboxes, then each connection will need to be recreated. This will need to happen whenever your mailbox moves or whenever the mailbox to which you are connecting moves. The first time you relaunch Outlook after either of these events you will be prompted to enter your password as the server attempts to recreate each connection.You will not know which connections the server is attempting to recreate; you will just see the same prompt for each connection that needs to be re-created. For example, if you have 2 connections to calenders in 2 other mailboxes and a connection to a shared inbox in a 3rd mailbox, then you will be prompted 3 times to re-enter your password. The prompt will look similar to the image below. You should check the box to Remember my credentials so that you won't be prompted again for each connection the next time you start Outlook unless your mailbox or the other mailbox moves again.
To minimize the number of times you need to go through this, we have identified mailboxes that have these cross connections and will move them together in the same batch wherever possible. This means you will just have to go through this only once in most cases instead of once when your mailbox moves and then again as each connected mailbox later moves. If you randomly receive a mailbox prompt days later after you have moved, it is probably because some other mailbox to which you are connected has not moved until then.
Instructions for configuring various email clients from scratch
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Windows
Configuring Outlook 2010/2013 for Windows with an Office 365 McCombs Mailbox
Mac
Configuring Outlook 2011 for Mac with an Office 365 McCombs Mailbox
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