Why does Unity crash when I build my game?

I am finally done with the first game I've been working on and after messing around with some export setting I was ready to build it. I made sure I had all my scenes in the build menu and I clicked build and selected a folder on my desktop. After 30 seconds an error message pops up saying Unity is not responding. When it checks for bugs it says no solution, found closing program. The whole program shuts down. I would just like to know could it be something in my settings, or is it my pc? I'm running a pretty old Dell pre-build with 24gb of DDR3 ram, an Intel i7-4790, 64 bit, and Windows 8.1. The rest is unknown but I know storage can't be the problem because I've got almost a whole terabyte empty plz help me this is my first game and I'm getting frustrated. (i'm only 13 btw)