m2e 1.6.2 (126.96.36.19950818-2354) RC1 for Mars has been released. It notably fixes a regression introduced in 1.6.1 that broke the groovy configurator. See the changelog here . It can be installed from . 3rd party configurator providers are *strongly* encouraged to check 1.6.2 works for them.
Unless new blocking issues are found for m2e 188.8.131.5250818-2354, it will most likely be released as-is next week.
m2e 1.7.0 (184.108.40.20650818-2353) M1 for Neon includes all the fixes from 1.6.2 plus initial Java 9 support . It can be installed from .
Java 9 beta support for Eclipse must be installed from the Marketplace.
Please note m2e 1.7.0 now requires JDK 8 minimum to run.
"Have you tried turning it off and on again" - The IT Crowd