Autodiscover errors - An explanation


Sometimes, you may get an error in Backup365 referring to an incorrect or unavailable Autodiscover record. This article explains why Autodiscover is used and why it is essential to work with Backup365.


You need to have a CNAME in your DNS zone file. It needs to be as follows:


CNAME: autodiscover.(yourdomain).com
Points to:

(You may need to change this if you aren't on the exch690 server. Go to then look up the client, click "Exchange servers and settings" to find the appropriate autodiscover record)


In general:
CNAME: autodiscover.(yourdomain).com
Points to:

However, your Office365 Autodiscover record can be different. If unsure, you can check this by exporting the zone file from you Office365 tenant.
Just go to and admin > Setup > Domains > click on domain > Required DNS settings > export

What Backup365 uses Autodiscover records for:

  • Backup365 requires a list of mailboxes to backup. Instead of extracting a list of mailboxes from the Exchange server directly, it uses the autodiscover on DNS to check the addresses.
  • By using this method, there is more flexibility in the instance that the server changes location or any configuration changes are made.
  • If no autodiscover record is present, Backup365 cannot verify the existence of the mailbox.