Allows email server autodiscovery with Outlook and Thunderbird on non-Exchange servers.
If you host an email server, you want it to be compatible with all kinds of clients. You don't want your end user to enter manually the email configuration for their email address.
With Thunderbird and software using the same standards, you can just use the autoconfig file. Sadly, on Outlook, Apple Mail and Apple phones, it doesn't work the same.
Outlook uses an undocumented, proprietary protocol called Autodiscover, that is made to only work on Outlook Exchange servers. This software attempts to reimplement this protocol, so your free-software based mail server works out-of-the-box with Outlook clients.
Apple mobile phones uses the mobileconfig file which is documented but very messy and incompatible with other "usual" installation methods.
- Apple Mail (check out #7 to see how it works)
- Outlook clients (2003, 2007, 2010, 2013) – partially tested
- Outlook clients (2016, 2019, Office 365), using Autodiscover V2 protocol
Git clone then build with Cargo, like a regular Rust application.
Run the application on your server, then make it listen to those two virtual hosts:
The best way to do so is to use a reverse proxy, which can also handle HTTPS.
You have to create a lot of DNS records to make autodiscovery work for all clients. Be sure to double check every entry.
mydomain.comwith your own domain.
220.127.116.11with your server's IP address.
On the mail server's domain
All of those entries should be recorded on your main domain.
autoconfig 86400 IN CNAME autodiscover.mydomain.com. autodiscover 86400 IN CNAME autodiscover.mydomain.com _imap._tcp 86400 IN SRV 0 0 143 mail.mydomain.com. _imaps._tcp 86400 IN SRV 0 0 993 mail.mydomain.com. _pop3._tcp 86400 IN SRV 0 0 110 mail.mydomain.com. _pop3s._tcp 86400 IN SRV 0 0 995 mail.mydomain.com. _smtp._tcp 86400 IN SRV 0 0 25 mail.mydomain.com. _smtps._tcp 86400 IN SRV 0 0 465 mail.mydomain.com. _submission._tcp 86400 IN SRV 0 0 587 mail.mydomain.com. _autodiscover._tcp 86400 IN SRV 5 0 443 autodiscover.mydomain.com
On a "customer" domain
Those entries should be added to any other domain using your mail server.
autoconfig 86400 IN CNAME autodiscover.mydomain.com autodiscover 86400 IN CNAME autodiscover.mydomain.com _autodiscover._tcp 86400 IN SRV 5 0 443 autodiscover.mydomain.com
You also need to generate a TLS certificate for each customer domain (specifically, for autoconfig and autodiscover subdomains).
This project is fully and shamelessly inspired of the following projects: