EssentialsX version (2.0.1-b546):

Server software (This server is running CraftBukkit version git-Spigot-21fe707-e1ebe52 (MC: 1.8.8) (Implementing API version 1.8.8-R0.1-SNAPSHOT)):

Server (logs/latest.log): https://gist.github.com/Lunatik934/f99c7371aecf172ac6916072990e7480

EssentialsX config (if applicable):

Are you using a shared host or running your server behind a firewall? It appears that your server is unable to reach Gist, so the kit can't be uploaded.

I use a server with firewall but the problem provide from java, use this method https://stackoverflow.com/a/40020183/4297304

The link is unrelated to this issue - this issue is a duplicate of #1214. If using dedicated hosting, please make sure your server is up-to-date, and try disabling your firewall. If using shared hosting, we cannot provide any assistance with this error.

Closing due to a lack of response; if this is still a problem, feel free to reopen the issue.