Office 365 Autodiscover not working

Siraj Hydrose 5

After a Tenant to Tenant Migration Autodiscover is not working. Migrated from a Tenant with Azure Ad Connect synced to the new tenant using BitTitan. Autodiscover is publish via DNS Registrar and updated, but outlook is not connecting.

Error:

Attempting to send an Autodiscover POST request to potential Autodiscover URLs.

Autodiscover settings weren't obtained when the Autodiscover POST request was sent.
Test Steps

The Microsoft Connectivity Analyzer is attempting to retrieve an XML Autodiscover response from URL https://autodiscover-s.outlook.com:443/Autodiscover/Autodiscover.xml for user user@domain.com .The Microsoft Connectivity Analyzer failed to obtain an Autodiscover XML response.
Additional DetailsAn error message was returned from the Autodiscover service XML response: <?xml version="1.0"?> <Autodiscover xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.microsoft.com/exchange/autodiscover/responseschema/2006"> <Response> <Error Time="20:34:28.4861487" Id="3560106202"> <ErrorCode>500</ErrorCode> <Message>The email address can't be found.</Message> <DebugData />

Glenn Van Rymenant 6 Reputation points

2024-04-28T10:10:13.1733333+00:00

Are you sure the email address is set correctly? Note that Outlook 16.0.6741.2017 and above has a feature called 'Direct Connect' which bypasses autodiscover altogether. So even if the autodiscover setup is incorrect, you should still be able to connect to the mailbox. (please check the address and whether Direct Connect is not disabled)
Loran Bruce 0 Reputation points

2024-04-29T01:24:04.6133333+00:00

We did a migration this weekend as well and are experiencing the exact same issue. Additionally, we can't preview or download attachments in OWA.
Glenn Van Rymenant 6 Reputation points

2024-04-30T09:14:30.7033333+00:00

Long shot, but you can query one of the endpoints used in AutoDetect, could you check if the output of the below cmdlet has discrepancies when compared to a domain/tenant where autodiscover is working as expected? (replace the email address and note that it has to be an existing address)

(Invoke-WebRequest -Uri 'https://prod-autodetect.outlookmobile.com/detect?services=office365,outlook,google,icloud,yahoo&protocols=rest-cloud,rest-outlook,rest-office365,eas,imap,smtp' -Headers @{'x-email'='glenn@vanrymenant.eu'})

One of the things I have run into during migrations is that when you migrate from a different platform (e.g.: Google Workspace), that this record is updated infrequently (according to MS support every 24 hours but last time it took 4 days to change) and that the provider remains on Google for a while. When migrated users open Outlook and enter their email address, Outlook will look for this record and propose setting up a connection to your Google mailbox, users then have to select the "Not google?" option in the prompt to open their Microsoft mailbox.
Noah Ma-MSFT 765 Reputation points Microsoft Vendor

2024-05-01T09:53:57.1766667+00:00

Just checking in to see if above information was helpful.

If the issue has been resolved, please mark the helpful replies as answers.