[Migrated from MSDN Exchange Dev] outlook error exchange must be online or connected after migrate active directory server from 2008 r2 to 2016

Question

Note: This case is migrated from MSDN Exchange Server Development forum. Since Exchange Server Development forum mainly discuss issues about Exchange development, and non-developer Exchange has transitioned to Microsoft Q&A for support, we migrated this non-developer question manually to continue the discussion.

Original Post: https://social.msdn.microsoft.com/Forums/office/en-US/27460162-26ac-4196-8b9a-2eae04d113ed/outlook-error-exchange-must-be-online-or-connected-after-migrate-active-directory-server-from-2008?forum=exchangesvrdevelopment

hello,

My problem is my all users cann't connecte with outlook but can connecte with owa

infrastructure

two domain contoller

exchange server 2013

Answer 1

What's the detailed version of your Exchange 2013?
Does the DC with windows server 2008 R2 still exist in the environment?

Here are some suggestions for you:
1 > Flush the computer's DNS, then try to create a new Outlook profile to see if user can connect to the mailbox.

ipconfig /flushdns  

2 > With internal network, we can use the Test E-mail Autoconfiguration to known if Outlook can connect to AD for SCP objects.

1. Locate the Outlook icon in the notification area, hold the CTRL key, right click the icon, and then click Test E-mail AutoConfiguration.
2. Enter the user's email address, only choose Use AutoDiscover.
   
3. View the result on the Log tab.

You can post the screenshot of the Log page, and don't forget to cover the email address and domain name.

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