I just had a rather weird problem occur today. I hope this helps anyone else with the same issue.
I opened PrePro CS6 like I always do and after the initialization screen I get to the window that asks me which project do I want to open, I click the latest project and after the load bar fills up a windows message pops up saying that their was a problem loading PrePro and that windows will search for a solution to the problem and than I have to close PrePro. I tried opening it again and the same problem. I tried opening a different project and it crashed just the same again. I tried restarting my computer, again I got the same results. I restarted my computer again and tried opening all my other Adobe apps and they all worked fine. I opened PrePro again, tried opening my latest project and it crashed again. I opened PrePro one more time but this time I created a new project and didn't change any settings, PrePro opened and worked. So I went to file, open recent projects, and opened the latest project (the one I had been trying to opening all along) and presto, it opened and worked.