Mirvi

It's been a while since this was posted, but I'm gonna chip in the things I learned when I got the same error. I had the same situation, where I had hosted a server daily for me and my friends, until one day when I ran the usual .bat file, I got the error. Here's how I fixed the problem: If you've port forwarded your server, check your IPv4 address. For some reason mine had changed from .2 to .3 during the night, and after changing the porting for Minecraft and server to the new IPv4 address, the server launched like usual. When you created the new server, it his highly possible why it started working again was because you used the new IP, so copying over the server.properties file would cause the same error to apear. Hopefully this helps other people who get this error in the future.