Version Won't load

Put the summary of the bug you're having here

What I expected to happen was...:
The game would launch
What actually happened was...:
Game Output said:
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

Steps to Reproduce:
1. Use Win10 computer
2. Click play
3. Bingo