Recently we discovered that there are a couple of reserved query string parameters in Amazon's S3 service. Due to our architecture which serves course content from S3, the presence of these reserved parameters in the course will cause an error in serving the content. So, we must also tag these parameters as restricted in our own service.
The parameters in question are "acl","policy","location","logging","notification", and "versions".
If your course is experiencing issues of accessibility (resulting in authorization errors) and uses one of the above parameters, we recommend changing your course to use a different parameter name.