Hello @MatthewLove  Thanks for posting this in the Canvas Community!  I would not be able to tell you what is causing that to happen without being able to take a look at your specific example. It sounds like something it out of order when you try to sync your grade Passback. You appear to have covered all your bases in troubleshooting this.   It might be best to reach out to your school's admin or canvas support to have them look into the issue happening in your specific course. There might need to be something done on the Canvas side of things to get this assignment to start syncing as intended. Be sure to provide them with a link to your course, the assignment that won't sync and any additional information related to the grade sync error. They should be able to take a look into this and figure out why this is happening.    Hopefully this helps!  -Colton  ... View more