Players can't connect to my server

I created a bukkit server for myself and a few friends. First, I tried with Hamachi, entered the IP in the server file, and I could connect but no one else could. So I switched to port forwarding, entered the IP as 192.168.1.1XX. I could connect, no one else could. So I went onto my IP page (or whatever you call it) and set up port forwarding for my IP and port 25565 in both in and out. Still nothing. So I switched my IP over to what a website told me it was. Used port forwarding the same way as I did before, this time server tells me maybe something else is running on the port. There isn't. I searched a website to check if the port is open, and it is. I restarted my computer, still nothing. If I remove the IP from the server file, it starts the server correctly, and if I change the IP to 192.168.1.1XX it allows me to connect, but no one else. What is the problem?