How do I update my Droid 4 from 2.3.6 to 4.1 if the check for updates button isn't working?

[AC Question]

I get a notification "Sorry! The application Motorola Services (process com.motorola.service.) has stopped unexpectedly. Please try again." whenever I do the check for update. I have already tried doing a factory reset before trying to check for an update and I have also done the trick with holding down the power and down volume button.

I have a Droid 4 on the Verizon network and it is currently running 2.3.6 and I want to get it up to date with the newest version available to the phone.