Group Tasks missing for a group member

Hi,

We have a scenario where a group has several tasks assigned to it, but one of the group members cannot see any of them. The user says she has not logged in to the system since before the tasks were assigned, so that discounts the explanation that she rejected the tasks. The tasks have not yet been accepted by some other group members either (and they can still see the tasks in their task list).

What else could cause this?

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