I'm using Spigot 1.8, and when I stop my server and restart it, skins doesn't load, and if I try to use /setskin [player] again, it only say:

Queued name to uuid resolve
UUID was successfull resolved from the player name
The skin is now downloading

But no finish, and an error is dumped to console:

[11:41:47] [Craft Scheduler Thread - 2/WARN]: Exception in thread "Craft Scheduler Thread - 2"
[11:41:47] [Craft Scheduler Thread - 2/WARN]: org.apache.commons.lang.UnhandledException: Plugin ChangeSkin v0.8 generated an exception while executing task 459
at org.bukkit.craftbukkit.v1_8_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:56)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoClassDefFoundError: com/google/gson/Gson
at com.github.games647.changeskin.SkinData.serializeData(SkinData.java:124)
at com.github.games647.changeskin.SkinData.(SkinData.java:39)
at com.github.games647.changeskin.Storage.getSkin(Storage.java:199)
at com.github.games647.changeskin.tasks.SkinDownloader.run(SkinDownloader.java:30)
at com.github.games647.changeskin.tasks.NameResolver.run(NameResolver.java:53)
at org.bukkit.craftbukkit.v1_8_R1.scheduler.CraftTask.run(CraftTask.java:71)
at org.bukkit.craftbukkit.v1_8_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:53)
... 3 more

My server is in offline mode, if it help (i'm premium).

Spigot is required

Why do you even still run Craftbukkit? Spigot is nearly the same now. Since the Craftbukkit project is dead, it's continued by the Spigot developers here: https://hub.spigotmc.org/

This means you can use Spigot then too.

Sorry, I said

I'm using Spigot 1.8,...

Oh I'm really sorry,

could you post the your plugins list? Another plugin is hiding the embedded libraries.

What's your build number?

Build number:

git-Spigot-15fa8e1-17a3db7 (MC: 1.8) (Implementing API version 1.8-R0.1-SNAPSHOT)

Plugin list:

dynmap, WorldEdit, VoidWorld, TuxTwoLib, Buycraft, SpectatorPlus, SimpleMOTD, Multiverse-Core, ProtocolLib, ImageOnMap, PerWorldTab, iConomy, PermissionsEx, Simple-AutoSave, Skins, Multiverse-NetherPortals, CustomJoinItems, Multiverse-Portals, Vault, WorldChat, Actionbar, TitleManager, MultiInv, ChangeSkin, TNTRun, HolographicDisplays, CommandSigns, Citizens, ChestCommands, Quester, CommandNPC, AuthMe, MinigamesLib, MGSkyWars, MGOITC, MGDeathRun, MGSeaBattle

Thanks for helping me.

Found it. It's not a plugin. It's the server version. They added the library this plugin uses in 1.8.3. Is it possible for you to update to 1.8.3 or higher (e.g. 1.8.8)?

I tried it lots of times, but BuildTools throw an error
(log:

BuildTools

[email protected]
Attempting to build version: '1.8.9' use --rev to override
Could not get version 1.8.9 does it exist? Try another version or use 'latest'
java.io.FileNotFoundException: https://hub.spigotmc.org/versions/1.8.9.json
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at org.spigotmc.builder.Builder.get(Builder.java:481)
at org.spigotmc.builder.Builder.main(Builder.java:236)

)

Now I will try to download 1.8.3.
Thanks.

With version 1.8.8 throw another error, and doesn't update.
(log:

BuildTools
[email protected]
Attempting to build version: '1.8.8' use --rev to override
Found version
{
"name": "582",
"description": "Jenkins build 582",
"refs": {
"BuildData": "838b40587fa7a68a130b75252959bc8a3481d94f",
"Bukkit": "01d1820664a5f881665b84b28871dadd132deaef",
"CraftBukkit": "e1ebe524a78e27f6a2829ed4574fded3779094e1",
"Spigot": "e4d4710834f7b292bc496f41f1cf9ac363225c0e"
}
}

Pulling updates for C:\Users\altrisis\Desktop\old\server1.8\BuildData.git
Successfully fetched updates!
Checked out: 838b40587fa7a68a130b75252959bc8a3481d94f
Pulling updates for C:\Users\altrisis\Desktop\old\server1.8\Bukkit.git
Successfully fetched updates!
Checked out: 01d1820664a5f881665b84b28871dadd132deaef
Pulling updates for C:\Users\altrisis\Desktop\old\server1.8\CraftBukkit.git
Exception in thread "main" org.eclipse.jgit.api.errors.JGitInternalException: Exception caught during execution of reset command. {0}
at org.eclipse.jgit.api.ResetCommand.call(ResetCommand.java:230)
at org.spigotmc.builder.Builder.pull(Builder.java:515)
at org.spigotmc.builder.Builder.main(Builder.java:257)
Caused by: org.eclipse.jgit.errors.LockFailedException: Cannot lock C:\Users\altrisis\Desktop\old\server1.8\CraftBukkit.git\index
at org.eclipse.jgit.dircache.DirCache.lock(DirCache.java:224)
at org.eclipse.jgit.dircache.DirCache.lock(DirCache.java:301)
at org.eclipse.jgit.dircache.DirCache.lock(DirCache.java:267)
at org.eclipse.jgit.lib.Repository.lockDirCache(Repository.java:1052)
at org.eclipse.jgit.api.ResetCommand.checkoutIndex(ResetCommand.java:390)
at org.eclipse.jgit.api.ResetCommand.call(ResetCommand.java:203)
... 2 more

)
Thanks (another time)

Do you tried to start in a clean folder?

No, because I don't know if ALL my plugins, config, worlds, arenas,... will work in a new folder.

I will try it.

Thanks.

I thought about just building the server there and then copy it.

Reolved. Thanks.