Since the Team Fortress 2 update on October 5, some players have repeatedly experienced issues attempting to query or connect to our EU server.
This was caused by a sudden change to the A2S_INFO request in the server query protocol, which is used by Steam to request server info.

We are glad to announce that the issue has now been fully resolved and you should be able to connect to the server as usual again.
If you've deleted the server from your favourites in an attempt to fix the problem, feel free to re-add it:

steam://connect/raiden.redsun.tf:27015
steam://connect/raiden.redsun.tf:27015