After removing a SEP client from the SEP Manager, and then returning it back to managed, you receive an error when trying to quarantine the client.
No matching computer found for the given computer GUID or your administrator account does not have sufficient access rights.
This occurs because the sep_unique_id maintained by ATP becomes outdated after the SEP client is removed, and a new one needs to be generated by SEP Manager.
When adding a SEP client back to SEP Manager, wait at least 1 hour to let ATP get the latest SEP Endpoint info from the SEP Manager. Once ATP gets the updated data from SEP Manager, we can issue the quarantine command successfully.
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