Hi! I know there was already an issue exactly like this but I still didn't know how to fix it...

JAVA VERSION :
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
`java version "1.8.0_241"

Java(TM) SE Runtime Environment (build 1.8.0_241-b07)

Java HotSpot(TM) 64-Bit Server VM (build 25.241-b07, mixed mode)`
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

If you want the console log:

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
`[17:53:51] [Server thread/INFO]: Time elapsed: 7791 ms

[17:53:51] [Server thread/INFO]: Preparing start region for dimension 'world_the_end'/minecraft:the_end

[17:53:51] [Server-Worker-7/INFO]: Preparing spawn area: 0%

[17:53:52] [Server-Worker-7/INFO]: Preparing spawn area: 6%

[17:53:52] [Server-Worker-5/INFO]: Preparing spawn area: 42%

[17:53:53] [Server-Worker-3/INFO]: Preparing spawn area: 85%

[17:53:53] [Server thread/INFO]: Time elapsed: 1890 ms

[17:53:53] [Server thread/INFO]: [scriptcraft] Enabling scriptcraft v3.4.0-2019-01-20

[17:53:53] [Server thread/ERROR]: [scriptcraft] No JavaScript Engine available. ScriptCraft will not work without Javascript.

[17:53:53] [Server thread/INFO]: Server permissions file permissions.yml is empty, ignoring it

[17:53:53] [Server thread/INFO]: Done (26.786s)! For help, type "help"`
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
I am using Spigot 1.15.1 and BuildTools...
Any Idea? (I have your book btw)

OK! I figured it out, SWITCH TO CRAFTBUKKIT!

At this point, I think it's the server that's broken. Maybe instead of using the latest revision (java -jar BuildTools.jar --rev latest), you could use the 1.15.1 revision (java -jar BuildTools.jar --rev 1.15.1)? If not, maybe the java version is outdated? You can check the version by typing java -version into the command prompt. If not, I'm sorry that I can't help you and hb432. I also have the book.

At this point, I think it's the server that's broken. Maybe instead of using the latest revision (java -jar BuildTools.jar --rev latest), you could use the 1.15.1 revision (java -jar BuildTools.jar --rev 1.15.1)? If not, maybe the java version is outdated? You can check the version by typing java -version into the command prompt. If not, I'm sorry that I can't help you and hb432. I also have the book.

I have the 1.15.1 tho.. look

Do you think reinstalling java would help?