Hi there!

I was decorating the scenes and terrain beside my airport runway until I would put some grass with //replace 0 31:1 when my server crashed. After that, when I try to start up the server again it loads up fine, but when I try to log on it says: "Can't find player" and then it kicks me again and shuts down the server.

I have copied the log from when it began doing weird things:
[23:35:50] [User Authenticator #1/INFO]: UUID of player DKDesigneren is 8c08833a-2560-4a9b-872e-c256c9e084a0
[23:35:51] [Server thread/INFO]: Server permissions file permissions.yml is empty, ignoring it
[23:35:54] [Server thread/INFO]: Done (74,118s)! For help, type "help" or "?"
[23:35:54] [Server thread/INFO]: Starting remote control listener
[23:35:54] [Server thread/WARN]: No rcon password set in 'C:\Users\Mika\Desktop\Skrivebord\Mapper\MineCraft\MineCraft Servere\Min server\server.properties', rcon disabled!
[23:35:54] [Server thread/ERROR]: Couldn't load server icon
java.lang.IllegalStateException: Must be 64 pixels wide
at org.apache.commons.lang3.Validate.validState(Validate.java:826) ~[bukkit.jar:git-Bukkit-53fac9f]
at net.minecraft.server.v1_8_R3.MinecraftServer.a(MinecraftServer.java:594) [bukkit.jar:git-Bukkit-53fac9f]
at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:509) [bukkit.jar:git-Bukkit-53fac9f]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_73]
[23:35:55] [Server thread/INFO]: [Citizens] Loaded 10 NPCs.
[23:35:55] [pool-3-thread-7/INFO]: [AreaShop] Update from AreaShop V2.3.2#CUSTOM to AreaShop V2.4.0 available, get the latest version at http://dev.bukkit.org/bukkit-plugins/regionbuyandrent/
[23:35:58] [pool-3-thread-2/INFO]: [Vault] Checking for Updates ...
[b][color=#FF0000][23:35:58] [Server thread/INFO]: That player cannot be found[/color][/b]
[23:35:58] [pool-3-thread-2/INFO]: [Vault] No new version available
[b][color=#FF0000][23:35:59] [Server thread/INFO]: DKDesigneren[/127.0.0.1:58549] logged in with entity id 700 at ([Airport]224.19826542011498, 4.0, 76.5628433094188)[/color][/b]
[23:35:59] [Server thread/WARN]: Can't keep up! Did the system time change, or is the server overloaded? Running 4447ms behind, skipping 88 tick(s)
[23:36:00] [Server thread/ERROR]: Encountered an unexpected exception
java.lang.NoClassDefFoundError: Could not initialize class net.minecraft.server.v1_8_R3.CrashReport
at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:720) ~[bukkit.jar:git-Bukkit-53fac9f]
at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:335) ~[bukkit.jar:git-Bukkit-53fac9f]
at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:628) ~[bukkit.jar:git-Bukkit-53fac9f]
at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:536) [bukkit.jar:git-Bukkit-53fac9f]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_73]
[b][color=#FF0000][23:36:00] [Server thread/INFO]: Stopping server[/color][/b]
[23:36:00] [Server thread/INFO]: [SimpleRename] Disabling SimpleRename v9.5
[23:36:00] [Server thread/INFO]: SimpleRename disabled!
[23:36:00] [Server thread/INFO]: [AreaShop] Disabling AreaShop v2.3.2#CUSTOM
[23:36:00] [Server thread/INFO]: [ChestShop] Disabling ChestShop v3.8.12
[23:36:00] [Server thread/INFO]: [Citizens] Disabling Citizens v2.0.16-SNAPSHOT (build 1267)
[23:36:00] [Server thread/INFO]: [WorldGuard] Disabling WorldGuard v6.1.2;e38d98d
[23:36:00] [Server thread/INFO]: [WorldGuard] Shutting down executor and waiting for any pending tasks...
[23:36:00] [Server thread/INFO]: [Pixelator] Disabling Pixelator v1.2.1
[23:36:00] [Server thread/INFO]: [Pixelator] Plugin deactivated!
[23:36:00] [Server thread/INFO]: [Multiverse-Core] Disabling Multiverse-Core v2.4-b527
[23:36:00] [Server thread/INFO]: [Multiverse-Core] - Disabled
[23:36:00] [Server thread/INFO]: [EssentialsSpawn] Disabling EssentialsSpawn vTeamCity
[23:36:00] [Server thread/INFO]: [Vault] Disabling Vault v1.5.6-b49
[23:36:00] [Server thread/INFO]: [EssentialsAntiBuild] Disabling EssentialsAntiBuild vTeamCity
[23:36:00] [Server thread/INFO]: [Lift] Disabling Lift v54
[23:36:00] [Server thread/INFO]: Lift v54 is now disabled!
[23:36:00] [Server thread/INFO]: [EssentialsChat] Disabling EssentialsChat vTeamCity
[23:36:00] [Server thread/INFO]: [EssentialsProtect] Disabling EssentialsProtect vTeamCity
[23:36:00] [Server thread/INFO]: [Essentials] Disabling Essentials vTeamCity
[23:36:00] [Server thread/INFO]: [AsyncWorldEdit] Disabling AsyncWorldEdit v2.3.2
[23:36:00] [Server thread/INFO]: [AsyncWorldEdit] Disabled
[23:36:00] [Server thread/INFO]: [WorldEdit] Disabling WorldEdit v6.1.3;7a097ca
[23:36:00] [Server thread/INFO]: [AsyncWorldEditInjector] Disabling AsyncWorldEditInjector v2.3.0
[23:36:00] [Server thread/INFO]: [AsyncWorldEditInjector] Disabled
[23:36:00] [Server thread/INFO]: Saving players
[23:36:00] [Server thread/INFO]: DKDesigneren lost connection: Server closed
[23:36:00] [Server thread/INFO]: DKDesigneren left the game.
[23:36:00] [Server thread/INFO]: Saving worlds
[23:36:00] [Server thread/INFO]: Saving chunks for level 'world'/Overworld
[23:36:02] [Server thread/INFO]: Saving chunks for level 'world_nether'/Nether
[23:36:02] [Server thread/INFO]: Saving chunks for level 'world_the_end'/The End
[23:36:03] [Server thread/INFO]: Saving chunks for level 'MinVerden'/Overworld
[23:36:03] [Server thread/INFO]: Saving chunks for level 'DKDIndustriesHovedkontor'/Overworld
[23:36:04] [Server thread/INFO]: Saving chunks for level 'MeCraftGenskabt'/Overworld
[23:36:04] [Server thread/INFO]: Saving chunks for level 'Airport'/Overworld
[23:36:06] [Server thread/INFO]: Saving chunks for level 'HovedkontorTo'/Overworld
[23:36:06] [Server thread/INFO]: Saving chunks for level 'FreakyVillePrison'/Overworld

I hope someone can help me out here.. This issue really sucks. Btw, I have tried to start up the server several times, with the same problem.