I still have some social life with non-geek friends who keep using MSN for instant messaging. I’m currently using Finch, which is a libpurple-based IM. If you’re in a similar situation, so you probably came to this post due to a certificate error message from Microsoft servers when trying to start your Finch (or Pidgin).

All you need is download the following updated certificates from Pidgin website and replace them into your purple installation dir (probably in /usr/share/purple/ca-certs):

http://developer.pidgin.im/viewmtn/revision/downloadfile/cd236baf6d00f3e1561a40974ce1828b793ea187/share/ca-certs/Microsoft_Secure_Server_Authority_2010.pem

http://developer.pidgin.im/viewmtn/revision/downloadfile/cd236baf6d00f3e1561a40974ce1828b793ea187/share/ca-certs/Microsoft_Internet_Authority_2010.pem