After mailbox migration Outlook needs a new profile - and teammates do not see calender sometimes

Question

Dear community

We configured Exchange Hyybrid mode between our Exchange 2016 Server and Office365. I migrated my mailbox sucessfully to O365 but my local installed Outlook 2016 did not switch to the O365 Mailbox . I had to create a new profile in Outlook. We have here "cache mode > ALL" active so i had to download 1.5 GB for my new profile. We also have users who have 5-15GB in the mailbox so download for new .ost file would take much longer. An other user we migrated did not have this problem, his outlook connected sucessfully to Exchange online after the mailbox migration.

Is there a way / workaorund that i do not have to create new profiles in outlook in general or is this a issue that only some users could have ?

The other thing i noticed - after my mailbox was moved to Exchange Online, my teammate could not see my calendar -> message "could not be updated" in calendar view. My teammate then entered his password in a box that popped up and his outlook connected to Office 365 and showed my calender sucessfully.
An other teammate did not get this message box - he had to create a new profile for his own outlook to see my calendar.

Is there someone how knows a solution for that problem maybe ?

Thank you very much for your help.

Answer 1

Hi @IT Guy ,
After you migrate, will there be any errors when logging in to Outlook directly without re-creating the Outlook profile?

Regarding the calendar, your teammate needs to enter a password or re-create the outlook profile to see your calendar. I think their mailbox was not connected to Exchange online correctly before. Will their mailbox work normally without rebuilding the outlook profile or entering the password?

According to my test, I migrate a mailbox from on-premises Exchange server to Exchange online in hybrid environment. Afterwards, I can log in to the mailbox successfully without rebuilding the outlook profile.

I found a similar known issue. The cause of the issue is when the name of the pre-migration Autodiscover server is cached in your Outlook profile in the registry. You could refer to: After migration to Office 365, Outlook doesn't connect or web services don't work

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Answer 2

My teammate was not migrated, he added my calendar and in outlook and there was a message in Calendar view "could not be updated" - if then Outlook brings the pop-up message to enter password, my teammate could see my calendar without configure a new profile for his own outlook. Even after he restarted his outlook he could see my calendar without entering his password.

An other teammate did not see a pop up message, so he could not enter his password and he could never see my migrated calendar until he created a new outlook profile for himself.

Other migrated users see my calendar with no problem because we are both in O365.

I also found this website with the "last known good URL" i will try that out, the problem is, it is not always the same situation, some users can connect with current profile, some need a new one, this makes planing the migration quite complicated.

I will update here after the test with the "last known good URL"

Thank you for your help !

Answer 3

Hi @Tellenbach Stefan ,

Based on my test, after you finished the migration, the Outlook client will receive a pop-up:

But you don't have to re-type the credentials. And the shared calendar stays what it was.

What if user C add the calendar manually?

Best regards,
Lou

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Answer 4

Dear ZhengqiLou-MSFT and LucasLiu

We found a configuration error in our config. The Sharing Policy was not correct configured. We did not thought about that the sharing policy has two connection points - one in the cloud and one onprem on the Exchange Server. After configuring the second end of the Sharing Policy the calendar sharing and visibility works fine. Thank you very much for your help.

The other big problem, that some clients need a new outlook profile after their mailbox is migrated, is still present. After the Outlook message that ZhengqiLou-MSFT shows in his post, some Outlook do not connect to the mailbox that is migrated to the cloud (computer was restarted too).
Under "File" > "Account Settings" is still the old URL to the onprem Exchange and not to Office 365. When i create a new mail profile for the user with that problem, Outlook connects directly to O365 and works perfectly.

A solution for that would be awesome !

Thank you all for your time and efforts.

Answer 5

Hello ZhengqiLou

Thank you for your feedback. The website you mentioned says:

You are migrating the mailboxes from Exchange 2010 to Exchange 2013 or Exchange 2016. You can face the issue that users with Outlook are not connecting to the Exchange Server.

I am migrating from Exchange 2016 to Office365 - does this solution work for my situation too ? This would really surprise me when a restart of a local Exchange Service would solve this "connecting to the cloud" issue.

Thank you very much for your feedback