According to the announcement, a 209 error is: 209/210 - Patch Manifest Error
This error occurs when selecting the EU server. Users instructed to uninstall/reinstall client.
Trouble is, I've never attempted to join the EU server.
I have also never had to repair or reinstall. I've simply logged out, waited a few minutes then logged back in again. Presto, no error 209.
Wondering if anyone has the random error.