@Texor You have to update the jar. After two to three weeks, that message appears to tell you to check for updates. Just recompile the jar using Buildtools and replace your existing jar with the new one.
@Texor How did you get the server file if you did not use buildtools? The only way to get the jars are if you use buildtools (unless you are downloading the file, which you should not as it is illegal and you have no reason to trust them)
@Texor Follow this tutorial on how to use the BuildTools.jar resource. Do not use the website getbukkit.org as it is not the official source for Spigot and Craftbukkit releases.
@Texor Look to the right of the thread title for a button labeled Edit Thread and change the prefix to Solved.
