Yeah so I've had this issue for a while. Tried downgrading from 2.0 to 1.5.0 to see if that would fix it, no go.
The server listed on
http://www.unfgaming.net/sourcebans/ is online right now, yet it is showing as "Error connecting to server".
I Google'd this issue a few months back but I kept running into dead end threads where the resolution to the issue was never disclosed, or the OP never returned to provide further requested info.
Any ideas on what's causing this and/or how to fix it? Should I maybe just ditch SourceBans all together? Another fellow who I host a TF2 server for uses something called "SUM" and it stores bans in an SQLite database file.