Mirror mode greyed out?

[xlNick]

For some reason mirror mode is greyed out, says only available on java 8. How would i fix this?

[xlNick]

Checked my java version and its Version 8 Update 411. Still greyed out

[Czar]

It could potentially be using a newer version of java if you have multiple java versions installed, but either way I would recommend uninstalling 411 and going java 8 update 291/292 and uninstalling any higher javas