Cant join with 1.7 on 1.20 server

[linsaftw]

/viaversion dump Output

https://dump.viaversion.com/38dd9fe17230dd7fa32d463ee1279569f721f7e3ae25050acbd340c9a5ec40c6

Console Error

Client Error, No console error

---- Minecraft Crash Report ----
// Hi. I'm Minecraft, and I'm a crashaholic.

Time: 1/30/24 1:37 PM
Description: Unexpected error

java.lang.ClassCastException: yv cannot be cast to yz
at hp.a(SourceFile:51)
at bjb.a(SourceFile:499)
at hp.a(SourceFile:47)
at hp.a(SourceFile:12)
at ej.a(SourceFile:174)
at bje.e(SourceFile:212)
at bao.p(SourceFile:1306)
at bao.ak(SourceFile:774)
at bao.f(SourceFile:728)
at net.minecraft.client.main.Main.main(SourceFile:148)

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head --
Stacktrace:
at hp.a(SourceFile:51)
at bjb.a(SourceFile:499)
at hp.a(SourceFile:47)
at hp.a(SourceFile:12)
at ej.a(SourceFile:174)
at bje.e(SourceFile:212)

-- Affected level --
Details:
Level name: MpServer
All players: 1 total; [bjk['LinsaFTW'/28, l='MpServer', x=1094.63, y=-58.38, z=-1533.46]]
Chunk stats: MultiplayerChunkCache: 12, 12
Level seed: 0
Level generator: ID 01 - flat, ver 0. Features enabled: false
Level generator options:
Level spawn location: World: (1101,-61,-1543), Chunk: (at 13,-4,9 in 68,-97; contains blocks 1088,0,-1552 to 1103,255,-1537), Region: (2,-4; contains chunks 64,-128 to 95,-97, blocks 1024,0,-2048 to 1535,255,-1537)
Level time: 1198599 game time, 1198599 day time
Level dimension: 0
Level storage version: 0x00000 - Unknown?
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Forced entities: 5 total; [yv['Villager'/17, l='MpServer', x=1104.50, y=-58.44, z=-1551.50], wo['Pig'/6, l='MpServer', x=1060.75, y=-60.00, z=-1522.72], wi['Donkey'/10, l='MpServer', x=1074.41, y=-60.08, z=-1505.34], bjk['LinsaFTW'/28, l='MpServer', x=1094.63, y=-58.38, z=-1533.46], wp['�ex2'/15, l='MpServer', x=1099.50, y=-60.08, z=-1511.72]]
Retry entities: 0 total; []
Server brand: FlameCord <- Purpur
Server type: Non-integrated multiplayer server
Stacktrace:
at bjf.a(SourceFile:289)
at bao.b(SourceFile:1972)
at bao.f(SourceFile:742)
at net.minecraft.client.main.Main.main(SourceFile:148)

-- System Details --
Details:
Minecraft Version: 1.7.10
Operating System: Windows 8.1 (amd64) version 6.3
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 95963368 bytes (91 MB) / 419430400 bytes (400 MB) up to 2147483648 bytes (2048 MB)
JVM Flags: 9 total; -XX:+DisableExplicitGC -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=16M -Xmx2048m -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.7.10
LWJGL: 2.9.1
OpenGL: NVIDIA GeForce RTX 3050 Ti Laptop GPU/PCIe/SSE2 GL version 4.6.0 NVIDIA 546.17, NVIDIA Corporation
GL Caps: Using GL 1.3 multitexturing.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Anisotropic filtering is supported and maximum anisotropy is 16.
Shaders are available because OpenGL 2.1 is supported.

Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: []
Current Language: English (US)
Profiler Position: N/A (disabled)
Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Anisotropic Filtering: Off (1)

Bug Description

Cant join with 1.7

Steps to Reproduce

Login with a 1.7 client

Expected Behavior

Being able to login with no errors

Additional Server Info

I use FlameCord, the plugins are installed in spigot 1.20. Issue is not happening on 1.8. I sometimes get an empty world.

Checklist

• Via plugins are only running on EITHER the backend servers (e.g. Paper) OR the proxy (e.g. BungeeCord), not on both.
• I have included a ViaVersion dump.
• If applicable, I have included a paste (not a screenshot) of the error.
• I have tried the latest build(s) from https://ci.viaversion.com/ and the issue still persists.
• I have looked at https://www.spigotmc.org/resources/viarewind-legacy-support.52924/ and it does not offer a fix for my problem

[Barvalg]

[HowardZHY]

#447
EntityVillager can't cast to EntityPlayer

[FlorianMichael]

Can you send me the server log, especially the one when the world is empty?

[linsaftw]

Can you send me the server log, especially the one when the world is empty?

C:\Users\LinsaFTW\Documents\Minecraft Server\1.20 - Lobby>java -Xmx1G -jar Purpur.jar nogu
Starting org.bukkit.craftbukkit.Main
System Info: Java 21 (OpenJDK 64-Bit Server VM 21.0.1+12-LTS) Host: Windows 11 10.0 (amd64)
Loading libraries, please wait...
[15:22:13 INFO]: Environment: Environment[accountsHost=https://api.mojang.com, sessionHost=https://sessionserver.mojang.com, servicesHost=https://api.minecraftservices.com, name=PROD]
[15:22:15 INFO]: Loaded 1174 recipes
[15:22:15 INFO]: Loaded 1271 advancements
[15:22:15 INFO]: Starting minecraft server version 1.20.2
[15:22:15 INFO]: Loading properties
[15:22:15 INFO]: This server is running Purpur version git-Purpur-2095 (MC: 1.20.2) (Implementing API version 1.20.2-R0.1-SNAPSHOT) (Git: 4f12f5d on HEAD)
[15:22:16 INFO]: Using 4 threads for Netty based IO
[15:22:16 INFO]: Server Ping Player Sample Count: 12
[15:22:16 INFO]: [ChunkTaskScheduler] Chunk system is using 1 I/O threads, 3 worker threads, and gen parallelism of 3 threads
[15:22:17 WARN]: [Pufferfish] Will not enable SIMD! These optimizations are only safely supported on Java 17, Java 18, and Java 19.
[15:22:17 INFO]: Default game type: SURVIVAL
[15:22:17 INFO]: Generating keypair
[15:22:17 INFO]: Starting Minecraft server on *:25566
[15:22:17 INFO]: Using default channel type
[15:22:17 INFO]: Paper: Using Java compression from Velocity.
[15:22:17 INFO]: Paper: Using Java cipher from Velocity.
[15:22:17 INFO]: [ViaVersion] Loading server plugin ViaVersion v4.10.0-24w04a-SNAPSHOT
[15:22:17 INFO]: [ViaVersion] ViaVersion 4.10.0-24w04a-SNAPSHOT is now loaded. Registering protocol transformers and injecting...
[15:22:18 INFO]: [ViaVersion] Loading block connection mappings ...
[15:22:18 INFO]: [ViaVersion] Using FastUtil Long2ObjectOpenHashMap for block connections
[15:22:18 INFO]: [ViaBackwards] Loading translations...
[15:22:18 INFO]: [ViaBackwards] Registering protocols...
[15:22:19 INFO]: [ViaBackwards] Loading server plugin ViaBackwards v4.10.0-24w04a-SNAPSHOT
[15:22:19 INFO]: [spark] Loading server plugin spark v1.10.59
[15:22:19 INFO]: [ViaRewind] Loading server plugin ViaRewind v3.0.6-SNAPSHOT
[15:22:19 INFO]: Server permissions file permissions.yml is empty, ignoring it
[15:22:19 INFO]: [ViaRewind] Enabling ViaRewind v3.0.6-SNAPSHOT
[15:22:19 WARN]: **** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!
[15:22:19 WARN]: The server will make no attempt to authenticate usernames. Beware.
[15:22:19 WARN]: Whilst this makes it possible to use BungeeCord, unless access to your server is properly restricted, it also opens up the ability for hackers to connect with any username they choose.
[15:22:19 WARN]: Please see http://www.spigotmc.org/wiki/firewall-guide/ for further information.
[15:22:19 WARN]: To change this, set "online-mode" to "true" in the server.properties file.
[15:22:19 INFO]: Preparing level "world"
[15:22:19 INFO]: Preparing start region for dimension minecraft:overworld
[15:22:19 INFO]: Time elapsed: 212 ms
[15:22:19 INFO]: [ViaVersion] Enabling ViaVersion v4.10.0-24w04a-SNAPSHOT
[15:22:20 INFO]: [ViaVersion] ViaVersion detected server version: 1.20.2 (764)
[15:22:20 INFO]: [ViaBackwards] Enabling ViaBackwards v4.10.0-24w04a-SNAPSHOT
[15:22:20 INFO]: [spark] Enabling spark v1.10.59
[15:22:20 INFO]: [spark] Using Paper ServerTickStartEvent for tick monitoring
[15:22:20 INFO]: [spark] Starting background profiler...
[15:22:20 INFO]: [spark] The async-profiler engine is not supported for your os/arch (windows11/amd64), so the built-in Java engine will be used instead.
[15:22:20 INFO]: Running delayed init tasks
[15:22:20 INFO]: Done (5.507s)! For help, type "help"
[15:22:20 INFO]: [ViaVersion] Finished mapping loading, shutting down loader executor!
[15:22:21 INFO]: [ViaVersion] You are running a development version of the plugin, please report any bugs to GitHub.
[15:23:06 INFO]: UUID of player LinsaFTW is 6e777127-0fa1-3452-a721-7318be135618
[15:23:06 WARN]: [ViaBackwards] Increased world height is NOT SUPPORTED for 1.16 players and below. They will see a void below y 0 and above 256
[15:23:06 INFO]: LinsaFTW joined the game
[15:23:06 INFO]: LinsaFTW[/127.0.0.1:59855] logged in with entity id 28 at ([world]1094.949382398599, -60.0, -1533.1340787864035)
[15:23:07 WARN]: [ViaBackwards] Ignoring plugin channel in incoming REGISTER: FML
[15:23:07 WARN]: [ViaBackwards] Ignoring plugin channel in incoming REGISTER: FORGE
[15:23:07 INFO]: LinsaFTW lost connection: Disconnected
[15:23:07 INFO]: LinsaFTW left the game

[linsaftw]

It happens without FlameCord installed also.