Hey MaplePrimes

I have been having a problem with almost all of my documents in maple. I have had a lot of notes and everything for my school on different documents, but I can't open them. When I want to open them, they show a little with "How do you want to open this file?" with the options "Maple Text, Plain Text, Maple Inputs" and I have tried them all, but my document won't show. It's really unfortunate because all of my school stuff is on these documents.