Autodiscover DNS records

Setting Up Autodiscover for Your Domain

To configure Autodiscover for your domain, you will need to add several DNS records. The first decision is whether to use the client's domain or a shared FQDN (Fully Qualified Domain Name) hosted on your server. Whichever you choose, ensure it is correctly set in the domain's Hostname field. In addition, make sure you have an SSL certificate for that hostname. When using advanced protocols with desktop or mobile clients (e.g., MAPI with Outlook, EAS with iOS Mail, etc.), it's a major requirement. Whichever direction you go, by default this is typically set to mail.{domain}.

For the purpose of this example, we’ll use:

Domain: domain.tld
Hostname: mail.domain.tld

Required DNS Records

Below are the essential DNS records for basic Autodiscover functionality. 

Additional Records for New Outlook (2024+) and IMAP Support

Recent versions of "New" Outlook (2024 and newer), particularly when using IMAP, may require additional SRV records. This is generally due to Microsoft routing all email through their own servers when sent through or received by the New Outlook. These follow the standard format:

_Service._Protocol.Name TTL IN SRV Priority Weight Port Target

Here are common examples:

_imap._tcp.domain.tld     3600 IN SRV 0 0 143 mail.domain.tld
_imaps._tcp.domain.tld    3600 IN SRV 0 0 995 mail.domain.tld
_pop._tcp.domain.tld      3600 IN SRV 0 0 110 mail.domain.tld
_pops._tcp.domain.tld     3600 IN SRV 0 0 993 mail.domain.tld

Optional Records (Calendar and Contacts)

These records are not strictly required but may enhance functionality for calendar and contact synchronization. (E.g., with CalDAV and CardDAV clients.):

_caldav._tcp.domain.tld     3600 IN SRV 0 0 80  mail.domain.tld
_caldavs._tcp.domain.tld    3600 IN SRV 0 0 443 mail.domain.tld
_carddav._tcp.domain.tld    3600 IN SRV 0 0 80  mail.domain.tld
_carddavs._tcp.domain.tld   3600 IN SRV 0 0 443 mail.domain.tld