Report a Bug???

Unity Engine
1

Hi Guys,
For some reason, any time I go to build now, I get a “Report a Bug” window pop up. So is there a more general possibilty for what this means? I have never experienced one before.

??

Edit.
I just remembered, that I had a scene level0. I deleted it tho. It is still in the build list. Would this cause a, “Report a Bug”? *currently away from 'puter.

2

So it turns out the build was stopping on a level. I removed THAT level and it built. Now to find out what is wrong in that level. Anyway to know why the build ceased on that level ? Besides just a regular console check?