Problem/Bug PermissionsEx-1.23.2 not working

Hello, I'm new to this and I'm very noob, I'm trying to run the plugin PermissionsEx-1.23.2 in bukkit 1.8.8 but it's impossible and I've tryed everything.
This is the error I get:
[00:43:12] [Server thread/ERROR]: Could not load 'plugins/PermissionsEx-1.23.2.jar' in folder 'plugins'
12 org.bukkit.plugin.InvalidDescriptionException: Invalid plugin.yml
13 at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:162) ~[minecraft_server.jar:git-Spigot-db6de12-18fbb24]
14 at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:133) [minecraft_server.jar:git-Spigot-db6de12-18fbb24]
15 at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugins(CraftServer.java:292) [minecraft_server.jar:git-Spigot-db6de12-18fbb24]
16 at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:198) [minecraft_server.jar:git-Spigot-db6de12-18fbb24]
17 at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:525) [minecraft_server.jar:git-Spigot-db6de12-18fbb24]
18 at java.lang.Thread.run(Thread.java:748) [?:1.8.0_202]
19 Caused by: java.util.zip.ZipException: zip file is empty
20 at java.util.zip.ZipFile.open(Native Method) ~[?:1.8.0_202]
21 at java.util.zip.ZipFile.<init>(ZipFile.java:225) ~[?:1.8.0_202]
22 at java.util.zip.ZipFile.<init>(ZipFile.java:155) ~[?:1.8.0_202]
23 at java.util.jar.JarFile.<init>(JarFile.java:166) ~[?:1.8.0_202]
24 at java.util.jar.JarFile.<init>(JarFile.java:130) ~[?:1.8.0_202]
25 at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:150) ~[minecraft_server.jar:git-Spigot-db6de12-18fbb24]
26 ... 5 more

Anyone can help me??