mc will not run

Put the summary of the bug you're having here
minecraft wont let me run it.
What I expected to happen was...:
Describe what you thought should happen here
i thought if i pressed play it would start up
What actually happened was...:
Describe what happened here
but what realy happend is that it said somthing about my graphics card
I have updated my graphics card alot! and it still doesnt work. I use a Nvidia gtx 860m graphics card. the game used to run fine but now it doesnt
i tried reformating and redownloading but it doesnt work