Error Unable to intercept a read client packet. (java.lang.IllegalArgumentException: Unable to find a field null with the type com.mojang.authlib.GameProfile in net.minecraft.network.protocol.login.PacketLoginInStart) occured in com.comphenix.protocol.injector.netty.ChannelInjector@45b31c5f.

528 | [19:53:18] [Netty Epoll Server IO #1/ERROR]: [ProtocolLib] INTERNAL ERROR: Unable to intercept a read client packet.
529 | If this problem hasn't already been reported, please open a ticket
530 | at https://github.com/dmulloy2/ProtocolLib/issues with the following data:
531 | Stack Trace:
532 | java.lang.IllegalArgumentException: Unable to find a field null with the type com.mojang.authlib.GameProfile in net.minecraft.network.protocol.login.PacketLoginInStart
533 | at com.comphenix.protocol.reflect.FuzzyReflection.getFieldByType(FuzzyReflection.java:397)
534 | at com.comphenix.protocol.reflect.accessors.Accessors.getFieldAccessor(Accessors.java:57)
535 | at com.comphenix.protocol.injector.netty.ChannelInjector.handleLogin(ChannelInjector.java:651)
536 | at com.comphenix.protocol.injector.netty.ChannelInjector.decode(ChannelInjector.java:584)
537 | at io.netty.handler.codec.ByteToMessageDecoder.decodeRemovalReentryProtection(ByteToMessageDecoder.java:510)
538 | at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:449)
539 | at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:279)
540 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
541 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
542 | at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
543 | at com.comphenix.protocol.injector.netty.ChannelInjector$2.channelRead(ChannelInjector.java:289)
544 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
545 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
546 | at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
547 | at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:327)
548 | at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:299)
549 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
550 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
551 | at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
552 | at net.minecraft.server.network.LegacyPingHandler.channelRead(LegacyPingHandler.java:90)
553 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
554 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
555 | at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
556 | at io.netty.handler.timeout.IdleStateHandler.channelRead(IdleStateHandler.java:286)
557 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
558 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
559 | at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
560 | at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410)
561 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
562 | at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
563 | at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919)
564 | at io.netty.channel.epoll.AbstractEpollStreamChannel$EpollStreamUnsafe.epollInReady(AbstractEpollStreamChannel.java:800)
565 | at io.netty.channel.epoll.EpollEventLoop.processReady(EpollEventLoop.java:487)
566 | at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:385)
567 | at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:995)
568 | at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
569 | at java.base/java.lang.Thread.run(Thread.java:833)
570 | Dump:
571 | Parameters:
572 | io.netty.buffer.PooledUnsafeDirectByteBuf@3e3bd77a[
573 | memoryAddress=140596609032208
574 | recyclerHandle=NOOP_HANDLE
575 | chunk=Chunk(5024d11: 1%, 24576/4194304)
576 | handle=1125929971613696
577 | memory=java.nio.DirectByteBuffer[pos=0 lim=4194304 cap=4194304]
578 | offset=16384
579 | length=1
580 | maxLength=16
581 | cache=io.netty.buffer.PoolThreadCache@233daa0
582 | tmpNioBuf=
583 | allocator=PooledByteBufAllocator(directByDefault: true)
584 | refCnt=2
585 | readerIndex=1
586 | writerIndex=1
587 | markedReaderIndex=0
588 | markedWriterIndex=0
589 | maxCapacity=2147483647
590 | ]
591 | manager:
592 | com.comphenix.protocol.injector.PacketFilterManager@2bb013b5[
593 | unhookTask=com.comphenix.protocol.injector.DelayedSingleTask@3c4db917
594 | packetListeners=[]
595 | packetInjector=com.comphenix.protocol.injector.netty.ProtocolInjector$5@203792e4
596 | playerInjection=com.comphenix.protocol.injector.netty.ProtocolInjector$4@5f892194
597 | inputBufferedPackets=[]
598 | recievedListeners=com.comphenix.protocol.injector.SortedPacketListenerList@740fbc6b
599 | sendingListeners=com.comphenix.protocol.injector.SortedPacketListenerList@255b26fc
600 | hasClosed=false
601 | classLoader=org.bukkit.plugin.java.PluginClassLoader@66ada867
602 | reporter=com.comphenix.protocol.ProtocolLib$1@39673001
603 | server=CraftServer{serverName=CraftBukkit,serverVersion=3553-Spigot-14a2382-ef09464,minecraftVersion=1.19}
604 | library=ProtocolLib v4.7.0
605 | asyncFilterManager=com.comphenix.protocol.async.AsyncFilterManager@26913e49
606 | knowsServerPackets=true
607 | knowsClientPackets=true
608 | phaseLoginCount=0
609 | phasePlayingCount=0
610 | packetCreation=false
611 | nettyInjector=com.comphenix.protocol.injector.netty.ProtocolInjector@7b494ee0
612 | pluginVerifier=com.comphenix.protocol.injector.PluginVerifier@2d1b4db0
613 | hasRecycleDistance=true
614 | minecraftVersion=(MC: 1.19.0)
615 | debug=false
616 | ]
617 | Sender:
618 | com.comphenix.protocol.injector.netty.ChannelInjector@45b31c5f[
619 | decodeBuffer=protected void net.minecraft.network.PacketDecoder.decode(io.netty.channel.ChannelHandlerContext,io.netty.buffer.ByteBuf,java.util.List) throws java.lang.Exception
620 | encodeBuffer=protected void net.minecraft.network.PacketEncoder.encode(io.netty.channel.ChannelHandlerContext,java.lang.Object,io.netty.buffer.ByteBuf) throws java.lang.Exception
621 | factory=com.comphenix.protocol.injector.netty.InjectionFactory@7dccef6d
622 | player=com.comphenix.protocol.injector.server.TemporaryPlayerInvocationHandler@2040556f
623 | updated=
624 | playerName=
625 | playerConnection=
626 | networkManager=net.minecraft.network.NetworkManager@a3c5da2
627 | originalChannel=[id: 0xaeacd353, L:/172.20.0.46:50520 - R:/50.83.112.61:51488]
628 | channelField=VolatileField [accessor=DefaultFieldAccessor [field=public io.netty.channel.Channel net.minecraft.network.NetworkManager.m], container=net.minecraft.network.NetworkManager@a3c5da2, previous=[id: 0xaeacd353, L:/172.20.0.46:50520 - R:/50.83.112.61:51488], current=com.comphenix.protocol.injector.netty.ChannelInjector$3@ddb662b, previousLoaded=true, currentSet=true, forceAccess=true]
629 | packetMarker={}
630 | currentEvent=
631 | finalEvent=
632 | unfilteredProcessedPackets=com.comphenix.protocol.injector.netty.PacketFilterQueue@49d556e7
633 | vanillaDecoder=net.minecraft.network.PacketDecoder@613cbd22
634 | vanillaEncoder=net.minecraft.network.PacketEncoder@6dfd79f8
635 | finishQueue=[]
636 | channelListener=com.comphenix.protocol.injector.netty.ProtocolInjector@7b494ee0
637 | processor=com.comphenix.protocol.injector.NetworkProcessor@58c0bba3
638 | injected=true
639 | closed=false
640 | cumulation=PooledUnsafeDirectByteBuf(ridx: 1, widx: 1, cap: 1)
641 | cumulator=io.netty.handler.codec.ByteToMessageDecoder$1@5c11d834
642 | singleDecode=false
643 | first=true
644 | firedChannelRead=true
645 | selfFiredChannelRead=true
646 | decodeState=1
647 | discardAfterReads=16
648 | numReads=0
649 | added=true
650 | ]
651 | Version:
652 | ProtocolLib v4.7.0
653 | Java Version:
654 | 17.0.2
655 | Server:
656 | 3553-Spigot-14a2382-ef09464 (MC: 1.19)

its all in red on Aternos plz fix this

same happened to me?

Same. Hopefully there's a fix soon...

Oh, I feel stupid. We need to use the dev build.

Use the latest dev build for Minecraft 1.19
Use the latest release for all other recent Minecraft versions

I've been having the same issue. Hopefully the dev build works.

I went and downloaded the latest build, and I have not had any error messages since.