The connection to the server 'webmail.domain.com' could not be completed.

Question

Hello,

Scenario:

We have set up a hybrid migration from on-premises to Exchange Online (EXO). The setup worked well for the past two weeks, and we managed to migrate mailboxes.

A few days ago, we experienced internet issues. Since then, all users' sync attempts have been failing to complete, and the migration endpoint shows connection issues.

What we have tried since then:

• Updated the migration endpoint account password as it had expired.
• Verified that the certificate is valid and correctly assigned (which was already confirmed since we successfully migrated accounts).
• Attempted to create and update migration endpoint credentials, but it failed due to connectivity issues.

When we run the Hybrid Configuration Wizard (HCW), it runs successfully. However, the test-connectivity test to the migration endpoints fails to establish a connection.

Please see the attached screenshots.HCW.png

Test-Connectivity.png

Answer 1

Hi @Jabulani Motloung ,

Based on your description, I suggest you could try the following to fix the issues:

Please confirm that the MRS Proxy is enabled and then restart your IIS "iisreset" to take the action effective by the following command.:

Get-WebServicesVirtualDirectory -Identity "Server\EWS (default Web site)" |fl Server,MRSProxyEnabled

Enable basic authentication on Web Services Virtual Directory by the following command:

Set-WebServicesVirtualDirectory -Identity "Server\EWS (default Web site)" –BasicAuthenticaition $true

 Also, please make sure your firewall allows the incoming connections on URL containing /ews/mrsproxy.svc;

You can also try to create a new migration point during the creation of the migration batch. Just fill in the fields, don't put in a direct URL, left it over to Autodiscover to see if it works.

For more information you could refer to the links below: Troubleshooting issues where the hybrid migration endpoint cannot be created | Microsoft Learn.

If you have any questions, please feel free to contact me.