Console Error Logs:
[00:59:20 ERROR]: [ProtocolLib] INTERNAL ERROR: Cannot load ProtocolLib.
If this problem hasn't already been reported, please open a ticket
at https://github.com/dmulloy2/ProtocolLib/issues with the following data:
Stack Trace:
java.lang.ClassCastException: class java.util.AbstractMap$SimpleEntry cannot be cast to class java.lang.Integer (java.util.AbstractMap$SimpleEntry and java.lang.Integer are in module java.base of loader 'bootstrap')
at com.comphenix.protocol.injector.packet.PacketRegistry.associatePackets(PacketRegistry.java:257)
at com.comphenix.protocol.injector.packet.PacketRegistry.createOldRegister(PacketRegistry.java:149)
at com.comphenix.protocol.injector.packet.PacketRegistry.initialize(PacketRegistry.java:286)
at com.comphenix.protocol.injector.packet.PacketRegistry.getClientPacketTypes(PacketRegistry.java:317)
at com.comphenix.protocol.injector.PacketFilterManager.(PacketFilterManager.java:211)
at com.comphenix.protocol.injector.PacketFilterBuilder.buildInternal(PacketFilterBuilder.java:185)
at com.comphenix.protocol.injector.PacketFilterBuilder.build(PacketFilterBuilder.java:177)
at com.comphenix.protocol.ProtocolLib.onLoad(ProtocolLib.java:203)
at de.jpx3.intave.t6.a(t6.java:26)
at de.jpx3.intave.t6.a(t6.java:11)
at de.jpx3.intave.t6.b(t6.java:34)
at de.jpx3.intave.IntavePlugin.onEnable(Native Method)
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321)
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:340)
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405)
at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugin(CraftServer.java:357)
at org.bukkit.craftbukkit.v1_8_R3.CraftServer.enablePlugins(CraftServer.java:317)
at net.minecraft.server.v1_8_R3.MinecraftServer.s(MinecraftServer.java:414)
at net.minecraft.server.v1_8_R3.MinecraftServer.k(MinecraftServer.java:378)
at net.minecraft.server.v1_8_R3.MinecraftServer.a(MinecraftServer.java:333)
at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:264)
at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:525)
at java.base/java.lang.Thread.run(Thread.java:842)
Dump:
Parameters:
[NULL]
Sender:
com.comphenix.protocol.ProtocolLib@3c41d05[
statistics=
backgroundCompiler=
packetTask=-1
tickCounter=0
unhookTask=com.comphenix.protocol.injector.DelayedSingleTask@74398383
configExpectedMod=-1
updater=com.comphenix.protocol.updater.SpigotUpdater@4e5900ac
redirectHandler=
commandProtocol=
commandPacket=
commandFilter=
packetLogging=
skipDisable=false
isEnabled=false
loader=org.bukkit.plugin.java.JavaPluginLoader@3302a17e
server=CraftServer{serverName=CraftBukkit,serverVersion=git-Spigot-21fe707-741a1bd,minecraftVersion=1.8.8}
file=D:\饥饿游戏\饥饿游戏快速房\plugins\ProtocolLib.jar
description=org.bukkit.plugin.PluginDescriptionFile@28100237
dataFolder=D:\饥饿游戏\饥饿游戏快速房\plugins\ProtocolLib
classLoader=org.bukkit.plugin.java.PluginClassLoader@2fd4fb1a
naggable=true
ebean=
newConfig=YamlConfiguration[path='', root='YamlConfiguration']
configFile=D:\饥饿游戏\饥饿游戏快速房\plugins\ProtocolLib\config.yml
logger=org.bukkit.plugin.PluginLogger@8e5661f
]
Version:
ProtocolLib v4.8.0
Java Version:
17.0.11
Server:
git-Spigot-21fe707-741a1bd (MC: 1.8.8)

[00:59:20 INFO]: [ProtocolLib] Enabling ProtocolLib v4.8.0
[00:59:20 ERROR]: ******************************************************
[00:59:20 ERROR]: *** ProtocolLib does not support plugin reloaders! ***
[00:59:20 ERROR]: *** Please use the built-in reload command! ***
[00:59:20 ERROR]: ******************************************************
[00:59:20 INFO]: [ProtocolLib] Disabling ProtocolLib v4.8.0
[00:59:20 ERROR]: Error occurred while enabling Intave v14.8.3 (Is it up to date?)
java.lang.NoClassDefFoundError: com/comphenix/protocol/utility/MinecraftVersion
at de.jpx3.intave.ld.(ld.java:8) ~[?:?]
at java.lang.Class.forName0(Native Method) ~[?:?]
at java.lang.Class.forName(Class.java:375) ~[?:?]
at de.jpx3.intave.oy.b(oy.java) ~[?:?]
at de.jpx3.intave.oy.d(oy.java) ~[?:?]
at de.jpx3.intave.oy.a(oy.java) ~[?:?]
at de.jpx3.intave.oy.a(oy.java) ~[?:?]
at de.jpx3.intave.oy.a(oy.java) ~[?:?]
at de.jpx3.intave.IntavePlugin.onEnable(Native Method) ~[?:?]
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321) ~[spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:340) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugin(CraftServer.java:357) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at org.bukkit.craftbukkit.v1_8_R3.CraftServer.enablePlugins(CraftServer.java:317) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at net.minecraft.server.v1_8_R3.MinecraftServer.s(MinecraftServer.java:414) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at net.minecraft.server.v1_8_R3.MinecraftServer.k(MinecraftServer.java:378) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at net.minecraft.server.v1_8_R3.MinecraftServer.a(MinecraftServer.java:333) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:264) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:525) [spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at java.lang.Thread.run(Thread.java:842) [?:?]
Caused by: java.lang.ClassNotFoundException: com.comphenix.protocol.utility.MinecraftVersion
at java.net.URLClassLoader.findClass(URLClassLoader.java:445) ~[?:?]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:101) ~[spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot-1.8.8-1.9-SNAPSHOT.jar:git-Spigot-21fe707-741a1bd]
at java.lang.ClassLoader.loadClass(ClassLoader.java:587) ~[?:?]
at java.lang.ClassLoader.loadClass(ClassLoader.java:520) ~[?:?]
... 20 more

Server Version:
This server is running CraftBukkit version git-Spigot-21fe707-741a1bd (MC: 1.8.8) (Implementing API version Unknown-Version)

As stated in the log: don't reload your server. And please note that the 4.8.0 version is no longer supported and will not receive any bug-fix updates anymore. Please switch to ProtocolLib v5 (if possible) to get support & updates.

Thanks for replying!
However I might meet another issue...
[22:58:07 INFO]: [ProtocolLib] Loading ProtocolLib v5.3.0-SNAPSHOT-723
[22:58:07 ERROR]: [ProtocolLib] INTERNAL ERROR: Cannot load ProtocolLib.
If this problem hasn't already been reported, please open a ticket
at https://github.com/dmulloy2/ProtocolLib/issues with the following data:
Stack Trace:
java.lang.ClassCastException: class java.util.AbstractMap$SimpleEntry cannot be cast to class java.lang.Integer (java.util.AbstractMap$SimpleEntry and java.lang.Integer are in module java.base of loader 'bootstrap')
at com.comphenix.protocol.injector.packet.PacketRegistry.associatePackets(PacketRegistry.java:514)
at com.comphenix.protocol.injector.packet.PacketRegistry.createOldRegister(PacketRegistry.java:182)
at com.comphenix.protocol.injector.packet.PacketRegistry.initialize(PacketRegistry.java:556)
at com.comphenix.protocol.injector.packet.PacketRegistry.getClientPacketTypes(PacketRegistry.java:604)
at com.comphenix.protocol.injector.PacketFilterManager.(PacketFilterManager.java:112)
at com.comphenix.protocol.injector.PacketFilterBuilder.build(PacketFilterBuilder.java:121)
at com.comphenix.protocol.ProtocolLib.onLoad(ProtocolLib.java:179)
at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugins(CraftServer.java:297)
at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:199)
at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:525)
at java.base/java.lang.Thread.run(Thread.java:842)
Dump:
Parameters:
[NULL]
Sender:
com.comphenix.protocol.ProtocolLib@5c6b72e0[
statistics=
packetTask=
tickCounter=0
configExpectedMod=-1
updater=com.comphenix.protocol.updater.SpigotUpdater@4e82c714
redirectHandler=
scheduler=com.comphenix.protocol.scheduler.DefaultScheduler@479e47e
commandProtocol=
commandPacket=
commandFilter=
packetLogging=
skipDisable=false
isEnabled=false
loader=org.bukkit.plugin.java.JavaPluginLoader@29e154f7
server=CraftServer{serverName=CraftBukkit,serverVersion=git-Spigot-21fe707-741a1bd,minecraftVersion=1.8.8}
file=plugins\ProtocolLib.jar
description=org.bukkit.plugin.PluginDescriptionFile@54819b59
dataFolder=plugins\ProtocolLib
classLoader=org.bukkit.plugin.java.PluginClassLoader@443d8ea
naggable=true
ebean=
newConfig=YamlConfiguration[path='', root='YamlConfiguration']
configFile=plugins\ProtocolLib\config.yml
logger=org.bukkit.plugin.PluginLogger@1ab7a5eb
]
Version:
ProtocolLib v5.3.0-SNAPSHOT-723
Java Version:
17.0.11
Server:
git-Spigot-21fe707-741a1bd (MC: 1.8.8)

Thanks again for your kind help!