Most third-party Messenger clients have gone offline temporarily

If you have been using BitlBee, Pidgin (or anything using its library, libpurple), Trillian or some other third-party instant messaging client that supports the msn protocol, you may have noticed over the past few hours that either your contact list is no longer accessible or you cannot sign in.

In BitlBee, you’ll see:
<root> msn – Logging in: Authenticated, getting buddy list
<root> msn – Login error: Connection timeout

In Pidgin, you’ll see it attempt to log in but get stuck at “Available – Connecting…”.  In Trillian, your contact list will just not appear.

The problem seems to stem from a change on Microsoft’s end about which application IDs are allowed to retrieve contact lists.  The ID used in the above clients is the applicationId (CFE80F9D-180F-4399-82AB-413F33A1FA11) from Windows Live Messenger 2008 (8.5).  When the client attempts to get the contact list, the server will reply with: Invalid Application Header Application ID is either not defined in database or blocked from access.

The Fix
The 2012 application ID key still works as do clients revived using Messenger Reviver.  If you’re wanting to re-compile any of these applications with source code, just edit the code to change the above ID to the 2012 one, 484AAC02-7F59-41B7-9601-772045DCC569.  Additionally, if you’re familiar with running python, you can use this python script to automatically patch your client (thanks dx for creating this).

For Pidgin users, you might consider using the msn-pecan protocol plugin, then setting up a new account as the WLM protocol in Pidgin.  This has several benefits, including avoiding the issue mentioned below.

UPDATE: Both BitlBee and Pidgin have both updated their source code trees, and Trillian has a new beta release.

Not showing online to your contacts
On some accounts, you will no longer show online to your contacts after changing the application ID.  This issue is being investigated, but does not affect the Microsoft Messenger clients revived using Messenger Reviver.  On Pidgin you can also use the msn-pecan protocol plugin to bypass the problem.

Meanwhile, despite “the end” of Messenger supposedly 12 days ago, the Messenger Service continues to hum along.