fallout nv help!

[Vatnize]

i tried to boot up Fallout Nv and i keep getting this error 51

when i spam play button i can get to main menu of the game but when i press play it just shows the same thing
i turned off firewall, verified files, cleared cache, and even deleted fallout nv and steam and re installed it but still it wont start if there is anything anyone could do to help me that would be awesome!