Is it always the same invoice layout? If so, maybe try another invoice template to see if it's restricted to a single template.
If it crashes on templates generally, what I would probably do in such a situation is try a repair:
and if this is unsuccessful, back up the company(s) to more than one location, uninstall Quickbooks and do a fresh installation. Using QB in the past (not recently) I always found that unless there is a hardware fault (which will usually affect other things too) a fresh install cleared up odd misbehavior. If I recall correctly the nuisance with this is that you may have to get a fresh installation code from Intuit/Quicken. I'm not up to date on how that works these days.
Edit: looks like if you don't have your installation code recorded, you can have it emailed to you.
Edited by Platypus, 25 August 2013 - 08:35 PM.