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.
WeBWorK Main Forum
System does not record student's grade or attempts
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