trynan

There are no other routers in front of it.

Yeah, I gave them my WAN IP but that one doesn't even work on my own computer. Undoing the change to the properties folder fixed the crash but it still doesn't work. I just now tried using Hamachi instead and just to get an IP from that. Now I can connect using the IPv4 address given to me from Hamachi but my friends can't. Any other ideas?

Yeah, I've checked that it's running on 25565. I tried something new, I put my external IP into the server properties file because I saw someone else do it in a video. Now, though, when I open the launch.bat file it pops up with an error. Additionally, I don't know if this is supposed to happen because I don't remember if it did back when I did all this in 2012/2013, but when I go to cmd and do ipconfig my external IP doesn't show up. If I look it up in google I can get it though. What does WAN IP mean?

I used to run a tekkit classic server for just my friends and myself (this was back in maybe 2013). We all just recently decided to try it again after not playing for a super long time and I tried to get my server back up but after port forwarding again none of us can connect to my external IP. This might not be the right place to ask this question, but there must be something I'm missing. I've tried to get a static IP address but one of my friends told me you only really need that if you plan to run a server 24/7, which I'm not planning to do. I've port forwarded and checked it a thousand times, it should work. I have no clue as to what the problem could be. I've also tried using Hamachi because my friends all have it but even that isn't working??? Can anyone point me in the right direction towards some guidance to figure this out because my friends all want to try out tekkit classic again. Thanks.