From time to time, a user emails our feedback address reporting that he tried to send a message and got this error:

Could not send; a connection error occurred.

And I never had an answer for those users, because it’s quite an empty error message (“a connection error”? What kind of connection error?) and I never heard anything from the other developers about it. So I always wondered what caused that error message.

Now I’ve found out.

A user on the IRC channel mentioned that he had received that error message. Specifically, he started out asking whether there was a way to “fix sending of URLs through MSN”. I asked for more info, and he revealed that he got the same error message when attempting to send a URL that had a .info domain. I tried a couple such URLs myself, with David‘s help, and confirmed his report—even http://growl.info/ doesn’t work.

The reason MSN gives for this censorship is that it’s to protect users from exploits that use certain URLs. The problem with this reason is that any URL could be an exploit URL; filtering by keyword just isn’t enough, because the attackers can always invent new filenames. The correct solution is simply to fix the exploits.

There’s nothing we can do about this because it’s done on the server. This also means that all clients are affected, not just Adium.

We now have a page on our wiki titled MSN Censorship which contains a (probably incomplete) list of strings that are known to get a message blocked. If you include one of these strings in your message, the message will not arrive and you’ll get the “connection error occurred” error message in your chat window.

If you’d like to not have these problems anymore, we suggest switching to Google Talk or Jabber. If you’re using Gmail/Google Mail, you already have a GTalk account; you need only set it up in Adium and get all your friends to switch. (And yes, as a couple of comments point out, you also have the option of using OTR encryption—but that only works if the contact you’re talking to is also capable of OTR. If they’re running Adium or Pidgin, then they are, but not if they’re using some other client, such as the official MSN client.)

(Sources include and . Joost de Valk is the user I mentioned above. If you use Digg, please .)