I need serious help please! i bought e books at my school book store and i follow the instructions given. i am told that i need to authorize my computer on adobe digital editions under "campus bookstore" which i did. When it comes to clicking on my dowload link of my e books to make them download on digital editions, an error message pops up saying if the app is already installed (which it is), i need to create an asssociation in the default app settings page. i do not understand this!! and i need these books right now so if anyone can help i would appreciate it!