Internal exception java lang illegalstateexception invalid characters in username как исправить

In this article I have told how you can fix this error of Minecraft – (Failed to connect to the server internal exception: java.lang.IllegalStateException: Invalid Characters in Username)

Before fixing this Invalid Username Error, we will know why this Invalid Characters in Username Error comes, after that we will fix this error.

Why does (Invalid characters in Username) error occur in Minecraft?

When you open any world by running minecraft java edition by Tlauncher, then you will get to see this (Failed to connect to the server Internal Exception: java.lang.illegalStateException: Invalid Characters in Username) problem.

The reason for this error to come is Username because if you have left space in Username in Tlauncher, then you get to see this problem due to not writing the name in Username correctly, so let us now know that this (Invalid Characters in Username ) How to fix the problem.

Fix Minecraft java.lang.illegalStateException: Invalid Characters in Username

So now we know how to fix this Minecraft Java Edition (Invalid Characters in Username) Error. There is a very easy way to solve this Minecraft Java Edition Errors, you have to first open your Tlauncher, after that whenever you write the name in username, you do not have to give space at all, you have to write name in the username simultaneously and As soon as you write name at once without leaving a space.

Then after that in Tlauncher you will see a box unchecked at the bottom, then you have to tick it there, so now this minecraft problem is fixed, now if you open any world in Minecraft Java Edition, there you will find this (Invalid Character in) username) problems will not be found, you can fix it like this (java.lang.illegalStateException: Invalid character in username) problem.

Note :- Please ignore 

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This guide will tell you how to Fix internal exceptions in java.lang.illegalstateexception invalid characters in the username. You just have to follow the simple steps below to fix it.

When the error occurs, you have to click on the Back to Server list button and then close Minecraft. Then on the launcher, you have to uncheck the account tick.

After this, launch the game and now your problem is fixed.

Expected behavior

I update my server to 1.18.2 build today. One of my player failed joining the server today. I am running offline mode, and his nickname is «情绪稳定», which is in chinese characters. He use windows system maybe.

This is the screenshot he provided:

raw log in console

[21:11:34 INFO]: com.mojang.authlib.GameProfile@c042137[id=<null>,name=������������,properties={},legacy=false] (/10.0.4.12:43010) lost connection: Internal Exception: java.lang.IllegalStateException: Invalid characters in username

Observed/Actual behavior

Steps/models to reproduce

join the (offline-mode)game with some chinese character as player’s name.

Plugin and Datapack List

[22:16:37 INFO]: Plugins (9): AuthMe, Boom, CoreProtect, DeadChest, LiveRecorder*, LuckPerms, ProtocolLib, TimeMachine*, UltimateTimber

Paper version

version info

> version
[22:12:57 INFO]: Checking version, please wait...
[22:12:58 INFO]: This server is running Paper version git-Paper-339 (MC: 1.18.2) (Implementing API version 1.18.2-R0.1-SNAPSHOT) (Git: 9b492cf)
You are running the latest version

### Other

If any further infomation needed, please notice me. Thanks for maintaining this project!

before 1.18.2 version, minecraft server(download page link here) won’t kick player if «online-mode» is set to «false» in server file «server.properties«, even player use unicodes in their name(chinese, korean, japanese words). now players with unicodes in names will get kiced with message «Internal Exception: java.lang.IllegalStateException: Invalid characters in username» even when «online-mode» has been set to «false«. this issue appeared since version 1.18.2. this also resulted in some special minecraft versions (such as NetEase’s China Edition) stuck forever before version 1.18.2.

instead of forcing players to use «legitimate» usernames from the source, please leave the checking authority of nicknames to third-party server software(spigot, paper, bungee). this will prevent players from tens of thousands of servers from playing the latest version.

This is definitely an issue that hopes to be fixed, it’s not a suggestion, because it has violated the previous program logic, «online-mode» itself is used to ignore crack detection, and now this function is invalid, and this should be hopefully fixed.