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An exception to this rule is if you are using case sharing. When you use case sharing, shared cases are NOT deleted when you delete either the user or the group. This behavior may change in the future for group deletion.
Warning: If you deleted a user, do not create another user with the same username. This can cause issues with your data.
Deactivating Users
In general, deactivating users is not a useful method for getting rid of data.
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