Office 365 (System Offices) - Microsoft Exchange Online Migration Information

Technology Services has announced the availability of Microsoft Exchange Online (Office 365). This system will replace the local Microsoft Exchange 2010/2013 system currently used by faculty, staff, and graduate students for email, contacts, and calendaring. This document will supply some information regarding the migration as well as some FAQs and known issues.

Microsoft Exchange Online Migration
Part of the 365 Suite

When is it happening?
The target completion date is November 2018.  Specific dates of migration are being considered as we work with each unit to select the best date to move accounts.

Where can I find further information?
Prior to migration, to find further information, feel free to review KnowledgeBase articles by clicking on the below link:

Document 81372 is unavailable at this time.

How will I know my mailbox has been migrated?
After migration you will receive the email below.  There is no action required by you at this time.

Office 365 (System Offices) (Windows) - Outlook Migration Prompts
After the migration, you may be prompted for credentials.  Make sure your email address ( is in the username field and enter your password.

Do not check the "Remember my credentials" box at this time.

Office 365 (System Offices) (Mac) - Migration Prompts

After the migration, you may see the following pop-up.  Click Always use my response for this server.  Click Allow to let Outlook configure itself.

If prompted for a username and password, enter your email address and NetID password.

What differences with my mailbox will I see after the migration?

Your Outlook Desktop Client will look the same. 
  • There is a new web address for accessing email on the web. 
  • You should be redirected from to the new login address. 

Select your Illinois exchange account

Enter your NetID or email address and password to sign in

By November 2018 you will need to verify your account with 2 Factor Authentication

After 2 Factor Authentication you will be taken to your exchange online account

What challenges have been reported with the migration?

  • Office 365 (System Offices) (Mac) - Creating a New Mac Profile Post Office 365 Migration
Some customers have stated that there are problems with their Outlook and access to email post migration. Post migration it may be necessary to delete a customer's Mac Outlook Profile to alleviate any issues customers may experience.  Instructions to do so can be found by clicking the below link. 

Document 85034 is unavailable at this time.
  • Office 365 (System Offices)  – Managing Group Membership
You can no longer manage group membership from Outlook. Due to the one-way sync structure of UOFI AD > Azure AD group membership changes cannot be made in Outlook when the mailbox is located on Exchange Online. Alternatives are using ADUC to manage membership in UOFI AD, switch to an Office 365 group, switch to a Sympa listserv or contact your IT Pro.

  • Office 365 (System Offices)  – Recover Contacts Post Migration
You may find that your contacts on your iOS device is missing.  Go to the following Link and use the steps outlined to recover your contacts on your iOS device.
Document 85469 is unavailable at this time.
  • Office 365 (System Offices)  - Calendar and Free/Busy

You may find that you can no longer see the details of calendars that are outside of your direct department if they have not migrated yet.  You should still be able to see free/busy time. After all departments have migrated this will no longer be an issue. At this time being able to view free/busy times on a calendar outside of your department has been found to be inconsistent.  Microsoft has been notified of the issue and we are hopeful for a fix soon.

  • Office 365 (System Offices) - Shared Mailboxes

It is recommended to migrate shared mailboxes at the same time as your departments individual accounts.  You will not have access to shared mailboxes that have not migrated. We encourage you to move these together to reduce impacts on workflows, etc.

  • Office 365 (system Offices) - Skype for Business
  • Outlook Integration Error or Exchange needs your credentials 
After a mailbox is migrated to Exchange Online some Skype for Business clients receive a warning about Outlook integration, see exclamation marks on the Conversations tab, or a yellow bar about credentials. Be sure to use for username. If that doesn't help, you can clear the client-side cache for Skype for Business.
  • Lync 2010 is prompting to download and install a MSI file from Microsoft
This additional software install is required to allow Lync 2010 to connect to Exchange Online.
  • Lync phone edition phones can't connect to Exchange Online
Office 365 will only allow TLS 1.2 connections (blocking the older SSL3, TLS 1.0/1.1) after October 2018 and currently there are no plans to update the older Lync phone edition IP phones software to support that type of secure connection. These phones will still be able to connect tour on premise Skype for Business systems, but visual voicemail, calendar access, and access to email contacts will stop working. While the University has approximately 4,000 of these phones, currently only about 100 of these devices are connected using this protocol and using these features.

Other Known Issues    
  • Known Issues can be found at the below link:

Document 81376 is unavailable at this time. 

Keywords:exchange migration email aits   Doc ID:86707
Owner:Tanya W.Group:University of Illinois System
Created:2018-10-12 10:27 CDTUpdated:2018-10-15 10:07 CDT
Sites:University of Illinois System
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