We've recently encountered some issues with our larger courses (>200 students). When instructors access the grade centre, intermittently they are unable to do so, seeing an error message. Refreshing/reloading the grade centre does not help. Sometimes a change of browser will help, sometimes not. We are managed hosted, and Blackboard have identified the grade centre is 'caching', and clearing the cache on the server end resolves the issue - temporarily. They've done this around 3-4 times in the last few weeks, so its not sustainable. Its affecting a range of courses. They reckon its due to the large number of students (200-1000) and number of columns (13-27).
Anyone else had this issue?
Error message displayed>
Error: The data received from the server is not correct and cannot be used to display the Grade Centre. Reload the Grade Centre in case the error is due to an intermittent communication issue.
TypeError: Unable to get property 'indexOf' of undefined or null reference