I have been having this problem with all my classes and all of my assignment uploads. I am not able to submit any of my assignments through Google Drive even when Google has both been authorized on my Canvas account and the file type is specified by the professor. This has been extremely frustrating as I am using my institution's Google account and am unable to upload any of my assignments. Every time I get past the selection page where I am able to choose the file I want to upload from my Drive, no file is accepted.