[16:22:05] [Server thread/ERROR]: Could not load 'plugins/SimpleClans.jar' in folder 'plugins' org.bukkit.plugin.InvalidDescriptionException: Invalid plugin.yml at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:162) ~[spigot.jar:git-Spigot-db6de12-18fbb24] at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:133) [spigot.jar:git-Spigot-db6de12-18fbb24] at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugins(CraftServer.java:292) [spigot.jar:git-Spigot-db6de12-18fbb24] at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:198) [spigot.jar:git-Spigot-db6de12-18fbb24] at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:525) [spigot.jar:git-Spigot-db6de12-18fbb24] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131] Caused by: java.util.zip.ZipException: zip file is empty at java.util.zip.ZipFile.open(Native Method) ~[?:1.8.0_131] at java.util.zip.ZipFile.<init>(ZipFile.java:219) ~[?:1.8.0_131] at java.util.zip.ZipFile.<init>(ZipFile.java:149) ~[?:1.8.0_131] at java.util.jar.JarFile.<init>(JarFile.java:166) ~[?:1.8.0_131] at java.util.jar.JarFile.<init>(JarFile.java:130) ~[?:1.8.0_131] at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:150) ~[spigot.jar:git-Spigot-db6de12-18fbb24] ... 5 more

Are you using the latest version? http://104.236.246.108:8080/job/SimpleClans/

Yes, I use the latest version

Could you please test if it happens on Spigot 1.12?
I'm at work right now.

I use a Spigot 1.8.9 server ...

I saw that in the log. This is why I asked you to test...

On my test server (local) it goes on the 1.12 as well as on the 1.8

https://pastebin.com/t4vJsDYk
Loads normally here.
May you send me your jar?

OK, I have now the whole server file downloaded and given on my LocalHost server - there everything works ...

So... This is not an issue?

Apparently not anymore ...