after exchange 2019 cumulative update 15, mailbox migration to exchange online stopped working

Question

after exchange 2019 cumulative update 15, mailbox migration to exchange online stopped working

Anonymous

after exchange 2019 cumulative update 15, mailbox migrations to exchange online stopped working. Does it have something to do with Extended Protection or whatever it's called? How can I make it work again?

It was working before, we were on CU12...

0 comments

1 answer

Your answer

Answer 1

Hi Braun, Thaddeus,

Thank you for posting your question in the Microsoft Q&A forum.

Extended Protection is enabled by default when installing Exchange Server 2019 CU14 or later, and there are some prerequisites or unsupported scenarios for Extended Protection. For example, Extended Protection can't be fully configured in a Modern Hybrid configuration (Exchange servers are published via a Hybrid Agent).

Currently, you can try to disable Extended protection temporarily to see if mailbox migration works again. This could help us to confirm if your issue is caused by Extended protection. Then you can check and meet all requirements before enabling extended protection again.

You can use a script and disable Extended protection for all Exchange servers:

.\ExchangeExtendedProtectionManagement.ps1 -DisableExtendedProtection

For more information about Extended protection and the script, please check:

Exchange Server support for Windows Extended Protection | Microsoft Learn

ExchangeExtendedProtectionManagement - Microsoft - CSS-Exchange

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Anonymous

2025-05-01T22:30:17.5266667+00:00

i tried to use the script and use the disable switch and it changed nothing. We still can't migrate using the Exchange Online GUI. I did read in other forums that maybe using all PowerShell might still work, and luckily I found that it did. We have a MSoft case open to have them help us make the GUI work again, and I will try and post results afterwards.
Cyril Huntjens 0 Reputation points

2025-06-17T13:39:28.7466667+00:00

After upgrade to CU15 it's not working for me either.

Getting this error when moving a mailbox from 365 back to on prem: "The call to mrsproxy.svc failed because no service was listening on the specified endpoint. Error details: There was no endpoint listening at mrsproxy.svc that could accept the message."

Wpmder if it works for you now via GUI. Otherwise I might have a different issue.

Share via

after exchange 2019 cumulative update 15, mailbox migration to exchange online stopped working

1 answer

Your answer