Adobe Digital Editions crashes when I access my Nook

I have been using Adobe Digital Editions 4.5 to put library books onto my Nook, however recently whenever I go to put books on my nook the ADE program crashes. It will even crash when I just try to look at the files on my Nook from ADE.
I've tried uninstalling and reinstalling, using ADE 3.0, restarting my computer as well as restarting my Nook. I haven't tried resetting my Nook as I was hoping there might be something else I could do.