Connection Failed

[ThereIsNoLand]

So not exactly sure where to look for connection problems and where to actually start a thread about this so I'm putting this here. I have been able to connect to plenty of Killing Floor's custom servers but I have trouble connecting to a few and particularly Guardian servers which i can't connect to at all and always resulted in a Connection Failed error which is quite unfortunate given that as far as I know Guardian has quite a few custom mods I'm interested in. If I can get any help with connection that would be appreciated.