Messages App has worked flawlessly for several years, just last week it stopped working. I haven't made any changes or new OS updates or installed new software to cause this. The weird thing is I connect to my VPN and BOOM all my messages update immediately. I'm dumbfounded...
MakBookPro 2013 (Model Identifier: MacBookPro10,2), Yosemite 10.10.3
MacBook Pro (Retina, 13-inch, Early 2013), OS X Yosemite (10.10.4)
There are a few threads in the forums describing this issue, it appears to be an internet backbone issue:
Problem connecting on video chat AIM account/Messages
These were originally thought to be Yosemite upgrade issues (which is why they're not posted in this community), but like you, I had the same issue even though I'm using older versions and haven't upgraded.
Also, see iChat/iMessages quit working most of the time a month ago
However, you're describing having problems with just text messages, right? Not video, audio or screen sharing? That's something else. Texting was still working for me.
In my case it started working again yesterday. Haven't tried today yet. If you're still having problems, are you using Jabber, or AIM or ?
Messages just stopped working (unless connected to VPN, then works)
