Try again now. Logs show the server had a full disk but it's not full now so I'm not sure what was happening earlier.
This is happening to me again right now.
I got the same error just a few minutes ago.
Something like: Publish failed: unrecognized response from the server. - 500.
I got this a few times. It is nothing new, but usually it works after two or three tries. Could anyone explain what that error means?
In itself, the error (500) essentially just means "the server encountered some form of problem, so your request couldn't be completed." It doesn't mean anything more specific, just that something's gone wrong on our end :-)
In the relatively near future a lot of these issues should hopefully go away - we're soon getting a new server with heaps more of everything (especially disk space!)