If you can't access a Google document or slide, etc., please try the following:
A.
Go to google.com and sign in with your CMS account.
Go to myaccount.google.com/permissions
On that page, look for "Google Drive LTI by Canvas"
Click on it and then click REMOVE ACCESS
Go back to Canvas
Try to open a Google file
You should see a a box with the word AUTHORIZE - Click that
B.
IF that is not successful, let's try clearing the cache (storage for certain files)
Clear Google Chrome cache:
Click on the 3 vertical dots in the upper right hand corner.
Then click Settings
Click Privacy and Security
Then click Clear Browsing Data
Click Time Range. From the drop down box, choose "All time"
Make sure ONLY Cached images and files has a check mark beside it. (You can unclick the other boxes if you need to)
Then click Clear Data
After you clear the Cache, sign out of Chrome, shut down, and then restart the Chromebook. Try again.
C. NEW! See the screen shots below. I'm sorry they look a little wonky - couldn't fit everything into one screen shot!