Forum Discussion
[Solution] Parallel // Provider Exchange & Office 365 // Autodiscovery issue
Found it after 18 hours ;-) This was a very helpful link:
https://support.microsoft.com/en-us/help/3211279/outlook-2016-implementation-of-autodiscover
EDIT --> THE SOLUTION!!! / it only works when login with the tenant.. user@xyz.onmicrosoft.com or when you changed primary email to user@<domain>.<tld.> it is till working. -------> AND!!! Made some registry tweaks see below
not sure what exactly the proper key is... 16.0 stands for Outlook 2016 - funny is when I delete the keys.. and even reconfigure mailbox no autodiscovery popups are comming. Condition is that I'm logged in with the Microsoft O365 tennant which is connected to the Mailbox.
[HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\AutoDiscover]
"EnableOffice365ConfigService"=dword:00000001
"ExcludeLastKnownGoodURL"=dword:00000001
"ExcludeHttpRedirect"=dword:00000001
"ExcludeHttpsRootDomain"=dword:00000001
"ExcludeHttpsAutoDiscoverDomain"=dword:00000001
From what I understood, your goal is not to have Exchange-Exchange Online hybrid configuration as it is usually understood. If you would build a real hybrid, you wouldn't need to worry about autodiscover at all.
Anyways, in your workaround 1, where did you change DNS record? Internal or external DNS? If they run on different servers, please double check that you have changed both records. It is also advisable to clear all DNS caches you might have (local computer, DNS server, etc.).
If you like to test whether the "workaround 1" works, you can also edit C:\Windows\System32\drivers\etc\hosts -file to add autodiscover record:
40.101.65.200 autodiscover.<domain>.<tld>
I got it working before I wrote my post (Headquarter still have the provider Exchange and we have the Office 365 Exchange) But still getting popups to enter credentials when Outlook Autodiscover (autodiscover.<domain>.<tld>) kicks in. Why does it kick in? Why does it do the stuff to me?
I knew before how to get Office 365 configured directly know even if autodiscover.<domain>.<tld> is pointing to a provider Autodiscover-Server - Workaround as above. DNS record should be untouched in that way that nothing is interfering with Headquarter Exchange. Maybe adjusting SPF properly.
It still seems to be a DNS issue. Your clients (Outlook) seems to be getting the wrong autodiscover record and therefore are prompted for credentials.
Have you tried Remote Connectivity Analyzer tools to check records, or SARA on your client PCs?
Thanks for your reply and your time you spend on my issue.
As I said, it is working - John can send and receive mails with iOS devices because the use of the direct connection to O365!
But still getting popups from Outlook because Outlook ist still looking for the wrong Autodiscovery-Server beside it had it configured with direct connection.
And this direct connection is wanted because our Headquarter should be able to work independently.
And yes I tried everything. Including SARA. ;-)
Anybody there who can tell me how to deactivate this continously accessing of Outlook to the wrong Autodiscovery-Server or have an different solution without interfering with the "parallel" Szenario?
As I said Outlook of John is working fine and it was directly configured by a different method Outlook is using >> direct connection >> beside.. I just have to click away the Popups.
So if I understand correctly, you are using the same domain? The easiest solution is to probably switch to a new domain/namespace and you should be even able to use a subdomain.
Even using the same domain should works, as long as you can update the targetaddress attribute of any of the affected users to point to user@tenant.onmicrosoft.com, so that all Autodiscover requests hitting the hosted Exchange server are being redirected to O365. Problem is, this might not be possible in a hosted configuration, or will require you to work with the hoster support to configure it.
Another workaround is to simply configure the accounts via their user@tenant.onmicrosoft.com account in Outlook. This way autodiscover should work correctly, and even if you see a credentials prompt it should be one-time only. Haven't played with this for a while though, so I'm not sure how it works with Modern auth in play...
In case I'm not understanding the whole picture, a copy of the ExRCA/Test E-mail autoconfiguration wizards should clear up any confusion, so make sure to obtain them and attach them to the thread.
Other than that, I can think of few more factors that play a role with Outlook 2016 as detailed here: https://support.microsoft.com/en-us/help/3211279/outlook-2016-implementation-of-autodiscover
In your case I would check for/exclude the local and last know configuration, and maybe even force the "O365 as priority".
