I've had this issue for over two weeks now. Any document that is not recent enough (over 30 days old), is not loading, and thus cannot be opened. It takes aaaaages (there's a loading circle that appears next to the file name that supposedly shows the progress, but it stays always the same, very close to 0%), and then suddenly an error pops up in my computer - "The operation was cancelled".

I've tried quitting the box app and opening it again, quitting the apps themselves (Preview, Microsoft Word, Adobe InDesign), but nothing fixes it. 

Help please! I can't work without my files.