Autodiscover records RRS feed

  • Question

  • I am trying to setup Office 365 for a pilot for our organization.

    We currently have Exchange 2007.

    One of the initial steps to setup Office 365 is to create some DNS records.  The autodiscover record has me stuck.

    Our external DNS provider already has a CNAME record for autodiscover for the existing on-premise exchange server.  And...a second CNAME record cannot be created for Office 365.

    Is it possible to change the current CNAME records to SRV, and then create the CNAME record for Office 365?  If so, what impact would that have with the existing exchange server?


    Wednesday, October 29, 2014 8:04 PM


  • No I don't think that would work, you'll end up with all the machines looking to the new Office 365 records rather than your existing ones.

    As explained here there's a set order in which Outlook goes through the list of ways it can check the autodiscover records, and looking for an record comes before looking for an SRV record.

    If your aim is to do this as a trial and see how well it works then I'd suggest not using your existing email domain anyway, since you wouldn't be able to properly test receiving or sending emails since the two installations would end up conflicting with each other. If you don't have another domain that you could use you could always setup the email on a subdomain, for instance rather than using which is currently used in your organisation, setup DNS records and configure 365 on instead. You can then setup the CNAME record, SRV record, MX records etc within as if it's the live domain, configure it in 365, have the mailboxes configured in your Outlook alongside your existing mailboxes if you wanted, without any risk of conflict and allowing you to properly test it.

    • Marked as answer by mclementin Monday, June 8, 2015 1:45 PM
    Wednesday, October 29, 2014 9:38 PM