Why is the factory reset loading so long?

I did a factory reset and now it's been on a loading screen for a while now. If I'm not mistaken after loading it should allow me to put my email in all that but like I said it's been loading for a while now, longer than it usually does for a factory reset. Initially the Xbox started giving me problems after what I assumed was a unsuccessful system update because it went on by itself and just stayed like that for hours. What should I do?

:)