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Hello,
After some time searching I now have to post my question here.
We are currently in the process of migrating the Exchange accounts from on-prem to Exchange Online. We now have the annoying problem that the Outlook login window keeps asking for login details. This apparently happens when an account from the cloud accesses an on-prem account and vice versa. Unfortunately, setting “AlwaysUseMSOAuthForAutodiscover” to 1 in the registry doesn’t help. Modern authentication is activated on both on-prem and cloud. The tests on MS's test connectivity page look okay. But we can't get rid of it.
If I turn off cache mode, the pop-up doesn't appear, probably because nothing is being synchronized in the background.
On the on-prem side there is an Exchange 209 with CU13.
I hope someone here has an idea. We can always click away from the popup and then Outlook will connect again, but it's just very annoying.
The administration of a hybrid deployment that connects on-premises Exchange Server with Exchange Online, enabling seamless integration and centralized control.
This is a known issue that can occur during a hybrid deployment of Exchange on-premises and Exchange Online.
Good Luck!
Did you clear the cached credentials from Control panel for the user account?
As a test, can you edit the hosts file and add the Autodiscover record for exchange online and see if you still get any popups?
Also Corrupt profile may cause the problem, try to recreate OST file. If it can fix the issue.
Hi @Jörg Mai,
Thank you for posting to Microsoft Community. We are happy to help you.
Based on your description, I understand the issue is the Outlook continually prompts for login. However, I am confused about what you said about “the cloud accesses an on-prem account and vice versa”. Could you kindly explain it to me for understanding and helping you better.
The login prompt issue can be caused by a variety of factors, including incorrect login credentials, outdated software, or a corrupted Outlook profile. Exclude attempts you've already made. You could perform comprehensive troubleshooting such as the following.
Also, could you kindly share the login prompt screenshot for the further investigation.
If there are anything else you need help, please feel free to reply to me.
Hi @Anonymous
I wanted to say that the problem with the popup exists both for users who are still onprem and access cloud mailboxes and also the other way around.
Since I can at least mitigate the popup problem with the cache function, I don't think it's due to a defective Outlook profile.
Regarding the add-ins, the behavior is the same. With all (2) add-ins and cache mode disabled, the popup hardly occurs at all.
The option “Always prompt for logon credentials” is not there, I had already checked that.
Strangely enough, I haven't received a popup so far today, even though cache mode is on.
Hi,
I am delighted to know that you do not suffer from the issue now.
Since the issue disappears and is not reproducible, we cannot further investigate it. Meanwhile, would you like to monitor the issue for another one week in case the issue happens again?
If there is anything else we can do for you, please feel free to inform us.
Just checking in to see if above information was helpful.
If the issue has been resolved, please mark the helpful replies as answers.
Hi,
i still have no problems. Tonight some mailboxes were migrated again. I'm curious to see whether I get any feedback about the popup here.
Hi,
I am so glad to know that the issue disappeared and didn't happen again.
Based on my experience, it could be possible to encounter pop-up issue since the mailbox have just migrated and some clients have not been updated to the latest configuration.
We have also encountered that have to rebuild the Outlook profile to update the configuration after migrated.
If there is anything else I can do for you, please feel free to inform me.
Also, if the answer is helpful, please click on ACCEPT ANSWER as it could help other members of the Microsoft Q&A community who have similar questions to reference.
Thanks for your understanding.
Just checking in to see if above information was helpful.
If the issue has been resolved, please mark the helpful replies as answers.
I have migrated all users and the problem is solved as expected.
THX all for you time.
I am glad to hear the problem is solved. If my answer is of any help to you, please click on ACCEPT ANSWER as it could help other members of the Microsoft Q&A community who have similar questions to reference. Thanks for your understanding.
Accepting an answer helps other community members to know the answer helped you. It is also a way to thank and recognize the person who helped you.