[MC-2555] Cannot Connect To Own Server While Not Online (LAN) / Playername being E-Mail address when offline

I can't connect to my own server while in offline mode while not connected to internet

it doesn't work for 1.4.2 & 1.4.4 error below

DON'T BOTHER ASKING IF I WAS ON VANILLA because i was and am on vanilla

Error:

FOR 1.4.2

C:\Users\Liam\Desktop\New folder>java -Xmx2048M -Xms2048M -jar minecraft_server.
jar nogui.
208 recipes
27 achievements
2012-11-08 17:23:57 [INFO] Starting minecraft server version 1.4.2
2012-11-08 17:23:57 [INFO] Loading properties
2012-11-08 17:23:57 [INFO] Default game type: SURVIVAL
2012-11-08 17:23:57 [INFO] Generating keypair
2012-11-08 17:23:58 [INFO] Starting Minecraft server on *:25565
2012-11-08 17:23:58 [WARNING] **** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!
2012-11-08 17:23:58 [WARNING] The server will make no attempt to authenticate us
ernames. Beware.
2012-11-08 17:23:58 [WARNING] While this makes the game possible to play without
 internet access, it also opens up the ability for hackers to connect with any u
sername they choose.
2012-11-08 17:23:58 [WARNING] To change this, set "online-mode" to "true" in the
 server.properties file.
2012-11-08 17:23:58 [INFO] Preparing level "world"
2012-11-08 17:23:58 [INFO] Preparing start region for level 0
2012-11-08 17:23:59 [INFO] Preparing spawn area: 37%
2012-11-08 17:24:00 [INFO] Done (2.094s)! For help, type "help" or "?"
java.io.IOException: Received string length longer than maximum allowed (23 > 16
)
        at dx.a(SourceFile:231)
        at cq.a(SourceFile:30)
        at dx.a(SourceFile:188)
        at bx.i(SourceFile:248)
        at bx.c(SourceFile:23)
        at by.run(SourceFile:101)
2012-11-08 17:24:13 [INFO] /127.0.0.1:50235 lost connection

For 1.4.4

C:\Users\Liam\Desktop\New folder\New folder>java -Xmx2048M -Xms2048M -jar minecr
aft_server.jar nogui.
208 recipes
27 achievements
2012-11-08 22:58:59 [INFO] Starting minecraft server version 1.4.4
2012-11-08 22:58:59 [INFO] Loading properties
2012-11-08 22:58:59 [INFO] Default game type: SURVIVAL
2012-11-08 22:58:59 [INFO] Generating keypair
2012-11-08 22:59:00 [INFO] Starting Minecraft server on *:25565
2012-11-08 22:59:00 [WARNING] **** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!
2012-11-08 22:59:00 [WARNING] The server will make no attempt to authenticate us
ernames. Beware.
2012-11-08 22:59:00 [WARNING] While this makes the game possible to play without
 internet access, it also opens up the ability for hackers to connect with any u
sername they choose.
2012-11-08 22:59:00 [WARNING] To change this, set "online-mode" to "true" in the
 server.properties file.
2012-11-08 22:59:00 [INFO] Preparing level "world"
2012-11-08 22:59:00 [INFO] Preparing start region for level 0
2012-11-08 22:59:01 [INFO] Preparing spawn area: 26%
2012-11-08 22:59:02 [INFO] Preparing spawn area: 53%
2012-11-08 22:59:04 [INFO] Preparing spawn area: 87%
2012-11-08 22:59:04 [INFO] Done (4.136s)! For help, type "help" or "?"

2012-11-08 23:01:23 [INFO] Unknown command. Try /help for a list of commands.

2012-11-08 23:01:23 [INFO] Unknown command. Try /help for a list of commands.
java.io.IOException: Received string length longer than maximum allowed (23 > 16
)
        at eg.a(SourceFile:236)
        at cz.a(SourceFile:30)
        at eg.a(SourceFile:193)
        at cg.i(SourceFile:249)
        at cg.c(SourceFile:15)
        at ch.run(SourceFile:93)
2012-11-08 23:01:44 [INFO] /127.0.0.1:54126 lost connection
stop
2012-11-08 23:02:12 [INFO] Stopping the server
2012-11-08 23:02:12 [INFO] Stopping server
java.net.SocketException: socket closed
        at java.net.DualStackPlainSocketImpl.accept0(Native Method)
        at java.net.DualStackPlainSocketImpl.socketAccept(Unknown Source)
        at java.net.AbstractPlainSocketImpl.accept(Unknown Source)
        at java.net.PlainSocketImpl.accept(Unknown Source)
        at java.net.ServerSocket.implAccept(Unknown Source)
        at java.net.ServerSocket.accept(Unknown Source)
        at hu.run(SourceFile:66)
2012-11-08 23:02:12 [INFO] Saving players
Closing listening thread
2012-11-08 23:02:12 [INFO] Saving worlds
2012-11-08 23:02:12 [INFO] Saving chunks for level 'world'/Overworld
2012-11-08 23:02:13 [INFO] Saving chunks for level 'world'/Nether
2012-11-08 23:02:13 [INFO] Saving chunks for level 'world'/The End
2012-11-08 23:02:13 [INFO] Stopping server

C:\Users\Liam\Desktop\New folder\New folder>pause
Press any key to continue . . .

Error For 1.4.5 According To Andrew Shulman

java.io.IOException: Received string length longer than maximum allowed (24 > 16)
at net.minecraft.server.Packet.a(SourceFile:236)
at net.minecraft.server.Packet2Handshake.a(SourceFile:30)
at net.minecraft.server.Packet.a(SourceFile:193)
at net.minecraft.server.NetworkManager.i(SourceFile:249)
at net.minecraft.server.NetworkManager.c(SourceFile:15)
at net.minecraft.server.NetworkReaderThread.run(SourceFile:93)

Linked issues

is duplicated by 13

MC-4148 cannot play lan games over ad-hoc mode Resolved

MC-9715 Lan - join kick Resolved

MC-9967 [SOLVED] Connection Lost from localhost Resolved

MC-4695 Client stops responding when connecting to vanilla server 1.4.5 Resolved

MC-10163 When in offline mode the client uses your email for your username. Resolved

8 more links

relates to 2

MC-16008 Customized Team Prefix on Multiplayer Resolved

MC-473 Linux users can't open to lan because it's binded to 127.0.0.1 Resolved

Attachments

Comments 32

kumasasa 2012-11-08T22:44:58Z

Try updating to client / server 1.4.4 (pre)

CubeTheThird 2012-11-08T23:12:36Z

you can also try, though I don't believe there will be a difference, using 'localhost' instead of the ip address you specified.

Liam Newell 2012-11-12T20:16:09Z

127.0.0.1 Comes before localhost. either way this bug is really annoying because i cant play on lan through my computer because of this

kumasasa 2012-11-25T10:42:32Z

Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Andrew Shulman 2012-11-26T04:00:28Z

This is still valid in the 1.4.5 release. However, the exception I recieved is:
java.io.IOException: Received string length longer than maximum allowed (24 > 16)
at net.minecraft.server.Packet.a(SourceFile:236)
at net.minecraft.server.Packet2Handshake.a(SourceFile:30)
at net.minecraft.server.Packet.a(SourceFile:193)
at net.minecraft.server.NetworkManager.i(SourceFile:249)
at net.minecraft.server.NetworkManager.c(SourceFile:15)
at net.minecraft.server.NetworkReaderThread.run(SourceFile:93)

EDIT: Just realized I posted the de-obfuscated stack trace. Either way, the error is the same. I can additionally post the obfuscated one, if desired.

EDIT2: More information is always better! Here's the obfuscated stack trace.
java.io.IOException: Received string length longer than maximum allowed (24 > 16)
at eg.a(SourceFile:236)
at cz.a(SourceFile:30)
at eg.a(SourceFile:193)
at cg.i(SourceFile:249)
at cg.c(SourceFile:15)
at ch.run(SourceFile:93)

22 more comments

Chris King 2012-12-11T02:04:10Z

I have experienced this bug as well and I have found that it is a problem when Minecraft is checking valid usernames. More than likely you have migrated to a Mojang account and use your email to log in. The email address is longer than the standard Minecraft username of 16 characters, in your case it's 24 characters long.

Liam Newell 2012-12-11T17:10:37Z

@Chris King
unfortunately that's whats wrong but a modified user name will change that

Michael Bielski 2012-12-29T18:20:57Z

This is still appearing as of 1.4.6.

CubeTheThird 2013-01-06T03:29:18Z

I have recently experienced this too. Can confirm.

Maarten Thijs 2013-01-17T12:17:04Z

still an issue in the latest snapshot. please update, mod anyone?

Maarten Thijs 2013-02-06T17:35:29Z

still an issue in the latest snapshot!

Daniel 2013-02-17T23:42:53Z

Confirmed for 13w07a

Tails 2013-02-18T00:07:32Z

Can confirm that this issue is caused by the playername beeing the e-mail address when offline thanks to MC-9967.

Maarten Thijs 2013-02-18T15:40:12Z

hey @Dinnerbone, my ticket got marked as a duplicate of this ticket.

but when you say you fixed this
is this also fixed?
https://mojang.atlassian.net/browse/MC-4148

thanks for taking a quick look! 🙂

Daniel 2013-02-26T19:39:04Z

he fixed it!😃

Tails 2013-03-02T22:23:16Z

Reopening since not fixed.

Petteri Huuskonen 2013-03-06T16:06:50Z

Confirmed in 12w10b. Unmodded client (as if it mattered). Here's an image of the error (I was using LAN mode BTW) http://db.tt/kd13lkNt

Tom Lee 2013-03-06T16:13:09Z

Confirmed in 12w10b

Do you mean 13w10b?

Petteri Huuskonen 2013-03-06T18:29:08Z

Ugh... Yes, just an honest typo.

Liam Newell 2013-03-06T18:32:57Z

so many popular people commenting on my bug post YAY.

Liam Newell 2013-03-06T18:34:52Z

DINNER BONE FOUND MY BUG POST YAY

Shay Rossignol 2013-03-10T19:22:45Z

Issue present in 1.4.7. Apparently switching to a Mojang account was a bad idea. How do I change this?

Erik Broes 2013-03-11T07:54:01Z

Are you using the our launcher to launch the game? I'm unable to reproduce :/

Tails 2013-05-27T23:52:28Z

Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Andrew Shulman 2013-05-28T00:21:24Z

This issue exists in 1.5.2. Steps to reproduce:

Start the Minecraft launcher.
Enter a username longer than 16 characters. I used "abcdefghijklmnopqrstuvwxyz".
Enter any password.
Click Login. The login will fail. Click "Play Offline".
Start a server in offline mode.
Attempt to connect to it.

Josiah Somani 2013-06-01T01:14:42Z

I know how to fix this! So, the email is supposed to come up on your screen due to no login so then Minecraft cannot connect to the MOJANG Minecraft Server which means you get no information! Only the info on the launchers screen! And yes, you should'nt be able to connect because your computer needs to connect to the internet for your Minecraft_Server appllication to run. And if that application has no internet it cannot connect. You will have to copy the world files and paste it into a minecraft world. The files are located here: %appdata%/.minecraft/saves. I hope I helped!

Andrew Shulman 2013-06-01T15:00:23Z

I'm not sure if you commented on the wrong issue accidentally but what you describe is not related to this issue. It is quite possible to start a Minecraft server without an Internet connection. It is also possible to connect to it as long as the username that you use in offline mode is not longer than sixteen characters.

Aden McKinley 2013-07-08T05:46:37Z

I get this on my localhost server but same error.

ALSO: None of the numbers match the email AND i logged on properly.

@Dinnerbone is this your fancy new auth system broken?

(1.5.2 server)

CubeTheThird 2013-09-26T02:59:02Z

Is this still a concern in the current Minecraft version 1.6.4 / Launcher version 1.2.5 ? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Tails 2013-11-28T20:02:29Z

No response, assuming no longer an issue.

aidan pallian 2014-04-13T02:22:59Z

This IS still an issue. i was kicked off my own server after placing a command block and ever since i can't get on. PLEASE help me

CubeTheThird 2014-04-13T02:44:47Z

@aidan, your issue is probably a different problem. I suggest you visit the Mojang Support Center for help about it.