Question

Is it possible to find POP3 server address for any given email id (like [e-mail])? If yes, please provide some guidance preferably in PHP or .Net.

Edit :
I get addresses by querying MX record but those are not always the same which people use to fetch their emails.

Answer 1

I don’t think you can “guess” the POP3 server for any email address and be right each time, no : the POP3 server can either :

• be something like pop.thedomainnameintheaddress
• or something totally different, like ssl.hostingcompany.com

In the first case, you could try to guess — and sometimes be right… But in the second, you don’t stand quite a chance.

You might want to take a look at Thunderbird 3 : I think it includes some auto-configuration mecanism about that : you enter your e-mail address, and it tries to find the POP server for your.

Not sure how it works, but I suppose there is a database containning that kind of informations, that Thunderbird sends requests to ; that would be the “best” solution, I’d say, as it can be updated without having to change Thunderbird itself, and doesn’t rely on “guessing”.

About Thundrbird’s autoconfiguration mecanism, here’s an interesting link : https://wiki.mozilla.org/Thunderbird:Autoconfiguration#Implementation — especially the third point, which links to a directory where you can find configuration files for lots of domains.

For instance : https://live.mozillamessaging.com/autoconfig/gmail.com

Gets you an XML file indicating how Thunderbird has to be configured for @gmail.com emails.

And there’s quite a couple of configuration files for other domains — so this might be an interesting idea, at least for “well-known” domains 😉

Of course, this doesn’t solve the problem for non-well-known domains…