happening to me too im just using an older version
So when i click play with my metro on launcher it crashes giving me:
Error: Could not find or load main class net.minecraft.client.main.Main
Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release
It seems other people have been getting this too and i have reinstalled minecraft and java idk what to do now
happening to me too im just using an older version
DoubleParallax is working on fixing that, just email him, he'll give you a fixed version.
The problem might be in the hacked client.
Try downloading a newer or update to date one.