Messages on Mountain Lion unable to send messages
Hi guys I'm hoping you might be able to help me as I've been unable to fix this myself but to be honest, there isn't much more I could think of doing.
I have Messages installed as part of Mountain Lion and it's been working fine until very recently. I can't remember when but about a week ago, it stopped working. I haven't really done anything out of the ordinary, though I did run the maintenance section of Onyx recently.
I can't seem to send any messages from Messages, though it does download the transcript if I'm using my iPhone (which is logged in to this as well).
The steps I've tried are:
1. Logging out, then back in again.
2. Logging out, restarting and logging in again.
3. Updating OS and setting to Airport (from 10.8.4 to 10.8.5 and the firmwire for my previous gen Airport Express)
The Airport Express is connected to another router which my brother uses for ethernet connection to the internet and as I mentioned, everything was working fine until recently.
In my search for answers I saw someone ask for a console log, so I have pasted mine directly following a message sending attempt. It can be found here: http://pastebin.com/T1s0bE8g
I am REALLY REALLY appreciative of any assistance anyone provides, so many times I've been looking for an answer and it's been deep within these forums.
Thanks in advance!
MacBook Air (11-inch Mid 2012), OS X Mountain Lion (10.8.5)