Have you tried to open the ports on the router for SK. This site tells you how to do so for your router http://portforward.com/english/routers/port_forwarding/Linksys/WRT54G2/S...

If that doesnt work, then I would try a DMZ. It can be found in the Applications and Gaming tab. This option is basically like a direct connection. all ports will be opened for your specific IP on the router. Use this option as a last resort. Although I do not recommend you use it long term, basically use it to troubleshoot.

You can find your IP address by using the command prompt:

Depending on your version of Windows (assuming your running Windows?)
• XP:
  Start --> Run --> type cmd. hit enter. --> A little black box with text should appear. Type ipconfig and hit enter. You should see some text output, one of which will say IP address. Write that down as you will need that to forward ports on your router and in the DMZ option.
• VIsta/7:
  Start --> type cmd and hit enter --> A little blak box with text should appear. --> do the same as above.

I would definitely check firewall settings as well. Again, for troubleshooting it is simpler to just disable it, then see if it works.

I will assume you have already been through the standard "Reinstall Spiral Knights and Java" routine. If not, then I would recommend you use Revo Uninstaller for that, as it has the ability to completely remove most if not all things associated with said program. Do the same for java. Revo can be found here http://www.revouninstaller.com/start_freeware_download.html

If none of the above work, then there is a strong possibility that your ISP is blocking the ports required by Spiral Knights to run properly ( as a safety precaution any ports not required by most everyday use applications and services tend to get blocked). I would give them a call and see if they can open them for you.

What kind of issues are you experiencing?

If it's connectivity issues, we seem to have touched all the bases there. Again aside from contacting your ISP, theres not much else we can do. If you can access the game from another PC on the same network, then that would narrow down our search a bit. Unless you are behind some sort of proxy, then that is a different story.

I'll need a tad bit more information to better assist you.

Check that you have upnp enabled. Make sure that you have the Router with Nat option enabled. The DMZ option is essentially bypassing your router without bypassing your router. The fact that you can connect if you bypass your router, means that something is getting blocked. I would try resetting your router.

Do ye have any torrents or downloads running?

i also experiencing this problem can some one help me and send me the step by step hot wo fix this thanks (i have wrt54g router) i spend a lot of money here i miss to play :<