Server shuts down shortly after starting

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  • So made a modded server a few days ago and played on it a few times, and today it just shut down a few seconds after joining it. It has been working perfectly for the last days. In the end of the log i get this message: "The state engine was in incorrect state SERVER_STOPPING and forced into state SERVER_STOPPED. Errors may have been discarded."

    Shortly before there were also multiple error messages including:"

    [17:38:59] [Server thread/ERROR] [net.minecraft.server.MinecraftServer]: Encountered an unexpected exception

    4579
    net.minecraft.util.ReportedException: Exception ticking world

    4580
    at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:762) ~[MinecraftServer.class:?]

    4581
    at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:397) ~[nz.class:?]

    4582
    at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:668) ~[MinecraftServer.class:?]

    4583
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526) [MinecraftServer.class:?]

    4584
    at java.lang.Thread.run(Thread.java:750) [?:1.8.0_362]

    4585
    Caused by: java.util.ConcurrentModificationException

    4586
    at java.util.HashMap$HashIterator.nextNode(HashMap.java:1469) ~[?:1.8.0_362]

    4587
    at java.util.HashMap$KeyIterator.next(HashMap.java:1493) ~[?:1.8.0_362]

    4588
    at net.minecraft.server.management.PlayerChunkMap.func_72693_b(SourceFile:114) ~[ou.class:?]

    4589
    at net.minecraft.world.WorldServer.func_72835_b(WorldServer.java:227) ~[oo.class:?]

    4590
    at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:756) ~[MinecraftServer.class:?]

    4591
    ... 4 more

    4592
    [17:38:59] [Server thread/ERROR] [net.minecraft.server.MinecraftServer]: This crash report has been saved to: /server/./crash-reports/crash-2023-02-02_17.38.59-server.txt"

    Followed by:"[17:38:59] [Server thread/INFO] [net.minecraft.server.MinecraftServer]: Stopping server"

    Any ideas how to fix this?

  • Do you have a backup of the world before facing the issue? If yes, restore the backup