Link to home
Avatar of adrecal
adrecal

asked on

[Solved] Autodiscover in Hybrid O365 - Exchange 2010

Hello :)

I have a Hybrid Office365/Exchange 2010 configuration. If I create a new mailbox on Exchange 2010 (onpremises) my autodiscover works fine inside my organization. If I configure this onpremises account on my Android phone its works fine (changing mail server from outlook.office365.com to mail.mydomain.com)

BUT....:

Outside my organization when I configure my Outlook 2016 (VLSC version, not Click to run version) and put my email and credentials a Office365 window pop-ups and my credentials are not accepted.

User generated image
My question: all new onpremises created mailbox (exchange 2010) need to sync to Office365 cloud too (even without license)??
ASKER CERTIFIED SOLUTION
Avatar of Michelangelo
Michelangelo
Flag of Italy image

Blurred text
THIS SOLUTION IS ONLY AVAILABLE TO MEMBERS.
View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
See Pricing Options
Start Free Trial
Avatar of timgreen7077
timgreen7077

where does the user mailbox reside? is the mailbox on-prem or o365?
Avatar of adrecal

ASKER

Michelangelo, you did the trick!!
Do you think I had followed this documentation of the DNS and had not noticed the observation about the hybrid environment?

To simplify:
Hybrid Office365/Exchange (2010, 2013, 2016...) NOT change your external DNS CNAME to autodiscover.outlook.com until you have all your mailbox on cloud.
Resolution: Revert back my external DNS (Linux Bind, blahrg) autodiscover CNAME to:

autodiscover TTL 3600 CNAME mail.mydomain.com (where mail.mydomain.com is my external url point to OWA)

Thanks guys, thank you Michelangelo. :-)
Avatar of adrecal

ASKER

Resolution: Revert back my external DNS (Linux Bind, blahrg) autodiscover CNAME to:

before:
autodiscover TTL 3600 CNAME autodiscover.outlook.com.

after:
autodiscover TTL 3600 CNAME mail.mydomain.com. (where mail.mydomain.com is my external url point to OWA. Look at final point ".")
Glad to have helped!