We've had similar problems here, although I don't know the exact details. One example seems to have been triggered by reopening a problem set, if that helps. Also, students occasionally lose the "Submit Answer" button even when they haven't reached the limit of their attempts. I know that one can arrange this deliberately, but it seems to be happening accidentally. Any suggestions anyone can provide would be greatly appreciated.
-- Robert
WeBWorK Main Forum
System does not record student's grade or attempts
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