We have discovered that both Blackboard and Moodle have the following issue with the Description field for the LTI link.
1. If there is a space at the beginning of the description field (Blackboard) or activity description field (Moodle), or if there are double spaces anywhere in the description field (Blackboard and Moodle), this u'\xa0' error appears. Make sure there are no spaces at the beginning of your description, and no double spaces in your description.
2. You will get this error if your course is unavailable. Please make your course available.
3. This error occurs if you copy and paste information into the description field. Please manually type your description into the designated field.
For instructions on editing the Description field in Blackboard, see the FAQ How do I edit the Description field for my LTI link in Blackboard?
For instructions on editing the Description field in Moodle, see the FAQ How do I edit the Description field for my LTI link (also called the Activity Description) in Moodle?