Thank you for your reply. On this website, I do not always get to give good news, and this is one of these times.
FERPA disallows schools to disclose educational records without the family's/student's consent. By exporting the school emails, the school is afraid that you may inadvertently violate FERPA, which would have them be held accountable.
But aside from this, the answer is based on a simpler doctrine. If it is a school account, it is their email. It does not belong to you. The employer can set limits on email use and sharing for their employee's email accounts that belong to the employer. When you leave, you lose the account and it belongs to the employer and stays with them.
So the school CAN do this, and state that employees cannot copy emails to an outside server, etc. This is not unusual.
So yes, they can enforce this rule.
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