New server stuck connecting on server list, but connect via console works

I am just in the process of copying my Killing Floor server from an old host to a new host and am having a strange issue.



The server shows up in the server list, and in my favourites when I add the IP, I can see all the details about the server, and they're all correct, there is no password etc.



However, when I connect via either the Internet of Favourites tab, I just get stuck on Connecting loading "index.rom". This is an issue that's usually found with firewall issues, but neither my client or the server is running a firewall.



Things get even more strange when I use the in-game console, if I type open [ip] then me and my friends connect to the server just fine.



The server IP in question is: 5.135.154.174

It is located in a datacentre with no firewall or anything running on or in front of it.



An output of netstat -a finds it listening fine on both ports 7707 and 7717 (and a few other ports, but I've removed them from the list):

Proto Recv-Q Send-Q Local Address Foreign Address (state)

udp4 0 0 *.7717 *.*

udp4 0 0 *.7707 *.*



The server console shows no indication that anybody is even trying to connect to it, unless they use the in-game console in which case you get:

Open myLevel Wed May 14 11:57:36 2014 [IP]:65085

New Player Pricetx id=76561198021469289



Here are some things i've tried:

- Using a completely fresh KillingFloor.ini

- Validating server files

- re-downloading the server

- restarting the server

- changing map

- deleting steam_appid.txt



My old server is still working just fine, with the same OS, version etc.



If anybody has any suggestions, I'd be glad to hear it, because I'm running out of ideas!



Thanks,



-Pricetx