Put the summary of the bug you're having here
What I expected to happen was Minecraft to open so I could play as usual.
The launcher crashed when the 'play' button was pressed. I updated to the newest launcher when prompted to at the top of my launcher window but the same issue was faced.
I don't have this problem on my environments:
-Windows 6.1 (Windows 7), amd64, jre 1.7.0_71 OR jre 1.8.0_25
Could the reporter fill in the environments field?