The software powering this discussion forum encountered an unexpected problem. We apologize for the inconvenience.

The error message above is what we came across the other day on a clients Discourse Server.

The response from every page was a 500 with that message, which doesn't give much on where to go to get a solution.

If you still have SSH access to the server you are hosting then you're in luck, it's a fairly straightforward fix (for us at least).

Manually update discourse and docker image to latest version

SSH into the server, assuming that you have System Administrator access

cd /var/discourse
./launcher rebuild app

That is essentially it.

The process will take between 5-20 minutes to go through, and a few times it will look as though it's frozed... give it time.