Very usefull and epic dude

Basically my game has been crashing a lot. It basically crashes but like not crashing in the way that like the game completely closes but the game bascially sends me to my desktop and i cant alt tab back in. not without trying also. Like i can alt tab in but it still just shows me my desktop as if i wasnt in the game. I've deleted my norton anti virus to see if that was the problem and it wasnt so im still just questioning why is this happening so much and is there a way to fix it