Plugin Disabling

[heavy steeple]

https://pastebin.com/b4HAGp3C

[carmine pewter]

redownload a fresh .jar

[desert hare]

You're using quite an old version of DeluxeMenus. Consider updating maybe?

[heavy steeple]

I'll try it now

https://pastebin.com/Ly7ASrmj

[spring mesa]

Possible Solution Found:

The plugin (or program) you are trying to use was compiled using a newer Java version than the one you using.
To find what version you need, start from 52 which is Java 8 and for example, 60 is Java 16. (8 + 8 = 16 => 52 + 8 = 60)

Barry's solution finder is still in BETA and will make mistakes.

[heavy steeple]

Need Java 16?