Adding Exchange ActiveSync configs to the Mozilla ISP DB?

Christian Rößner cr at
Fri Nov 30 19:04:07 UTC 2012


Am 30.11.2012 um 19:31 schrieb Kent James <kent at>:

> A SRV record has a big advantage over other methods (it does not require that a webserver exist at the domain name, or if it does exist it does not require the email admin group to administer either a subdomain or redirect at that site), so I would say that the SRV record is actually the preferred way to deliver an autodiscover URL.

the downside of SRV is that you may require a special type of SSL certificate (I just can not remember the correct word for it). Else a popup window might appear on the client side asking you to accept the redirect. We had customers that were yelling us at the phone to remove that. What I miss here is that Microsoft did not think about something like DNSsec, which would give enough trust level. So most of the time, redirect or SRV do ask for permission.

In my opinion Autoconfig with CNAME is somewhat more user friendly.

What I must admit is that I have not much knowledge about internals of a ActiveSync server. So specifying ASUrl is one thing, implementing the service behind that another.

AutoDiscover does not allow specifying more than one type of service. Let's say IMAP, POP or SMTP. Or even ASUrl. I found in the Autoconfig specs (freemail example) that you can specify multiple protocols of each type, which automx already supports (seems thunderbird itself ignores that at the moment, why?).

-Christian Rößner

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