I can run a world in single player, and yes, others can connect to the server. Now, I have tried everything in this thread, even uninstalling and wiping the folders and then redownloading everything from scratch. Absolutely no change. I have contacted the server maintenance in hopes they will help, they didn't respond to my ticket last week, so I'm sending another one. Telling them I haven't been able to use their product since I purchased it, and I haven't. It's mind blowing, I just want to play some tekkit with some friends of mine far away, honestly I don't see why it should be this much of a hassle.