Transitioning to UW Exchange Online

UW Exchange Online is now live and available to current UW Exchange Local users under the migration phase of the program. A systematic process is underway to move all current UW Exchange Local users to UW Exchange Online. While the transfer is taking place, you will be able to access and use calendars and email. You will still have the ability to see other UW Exchange Local calendars after you move to UW Exchange Online. 

While UW Exchange provides many benefits over UW Exchange Local, some capacity limits necessarily apply. For a summary of important  limits, see Limits of UW Exchange Online.

Preparing for the Move

Before your mailbox is moved to UW Exchange Online, please make the following preparations.

Remove Oversized Messages

If you have any messages in your mailbox that are larger than 25 MB, please move them to another storage location, as they may be deleted during the move. For information on finding and saving oversized messages, see Moving Oversized Messages From UW Exchange Local.

Outlook 2010 and 2013 Users Should Be Running in Cached Exchange Mode

If you are using Microsoft Outlook 2010 or 2013, please make sure that you are running Outlook in cached Exchange mode. To check this in Outlook:

  1. StepsActions
  2. On the File tab, click Account Settings.
  3. From the menu, click Account Settings again.
  4. On the E-mail tab, click Change, and then make sure that the Use Cached Exchange Mode box is checked. If you need to check the box, you will need to close Outlook and reopen it to make the change take effect.

Stop Viewing Shared Calendars

If you are sharing calendars with permissions greater than just Free/Busy, you or the user who shares your calendar might experience unexpected behavior after the move. To avoid confusion, stop viewing those calendars until after you and those that you share with are moved. For more information, see the workaround under Outlook repeatedly displays instruction to quit and restart.

Back Up Your Mailbox (Optional)

If you are using Microsoft Outlook 2010, 2011, or 2013, you can easily back up your mailbox before the move. This is not necessary, but you might feel more secure knowing that you have a local copy of all of your mail. For details on how to do this, see Moving Oversized Messages From UW Exchange Local.

How Do I Know that My Mailbox Was Moved?

  • Log in to OWA using the URL for UW Exchange Local:

If you are still on UW Exchange Local, you will be logged on in the usual way. However, if your mailbox has been moved to UW Exchange Online, you will see the following screen, which redirects you to the UW Exchange Online service.


Click the link as instructed to access your UW Exchange Online mailbox using Outlook Web App.

What to Expect After the Move

After a successful migration, Outlook appears the same as it did before the migration. You can use Outlook as you did before. The change is the server that is hosting your mailbox.

If Outlook is open when your mailbox is moved to UW Exchange Online, you will see a message in Outlook that a change has been made.


Close Outlook and then open it again, logging in with your UW Exchange user name in the format Your password is the one associated with your UW NetID.

In some cases, this dialog box appears several times at intervals. If this happens, continue clicking OK and restarting Outlook until you can verify that your mailbox has been moved to UW Exchange Online.

If You Have Trouble Logging In Through Outlook

The migration experience has not been consistent for all users, even those who have the same OS and mail client combination. If you cannot connect to UW Exchange after the move, try one or more of these workarounds:

  • Close and reopen Outlook several times. Sometimes this is necessary before achieving a successful first-time connection.
  • Connect to UW Exchange through Outlook Web App using the following URL:

Note: If you are prompted to set the time zone, select it from the dropdown list.

If you can log in using Outlook Web App but not Outlook, try re-creating your profile.

  • If you are using Outlook 2010 are not able to re-create your profile, it might be necessary install Office 2010 SP2 or upgrade to Outlook 2013, which provides the best experience with UW Exchange.

UW Lync and UW Exchange Online

After the move, you must connect to UW Exchange Online before you can resume using UW Lync.

Office 365 Top Navigation Bar

Some users observe that some links in the Office 365 top navigation bar are missing. This condition might persist for a day or so. Ultimately, you will see the full navigation bar, as shown here.



If you use a smartphone to access your UW Exchange account, you will need to delete and re-create your profile. See Re-creating Your Exchange Profile.

Known Issues

Known issues and workarounds for common problems are listed on Known Issues with UW Exchange Online.

Reporting Problems

Subscribe to the MSCA-testing Mailman list to report problems, ask questions, and see other users’ feedback.

Send feedback to

Last modified: June 12, 2014