I did set up a rule for incoming traffic in the firewall. I will try setting up one for outgoing traffic as well. I will also try disabling it. The standard server from minecraft.net works though, so it must be something specific to Bukkit.
It could very well be the firewall as mughi mentioned. Since the standard server allows people to connect, then the port is opening correctly, but the fact that a similar program doesn't allow connection would mean that a software firewall is not allowing that program to open the same port. Try adding both inbound and outbound rules for Java in the Windows firewall advanced settings for port 25565 using UDP and TCP(this probably means you will have made 4 rules all together, 2 for inbound java, and 2 for outbound java).
Ok.. I turned off the firewall, and I think it might be working now. I can at least see myself on canyouseeme. Seems kinda stupid, since I made rules in the firewall for port 25565. Oh well.. if it works, it works. Can someone try logging in to see if it works?
Hey guys, i'm having a problem too.. I port forwarded my server. It was working for some months but after, I cant connect nor my friends can. But typing "localhost" makes me connect. PLEASE HELP MEEEE (I've checked my 192.168.1.1 . Everything in shape.)