No because it was on the school and bussinesses computer. Yes unless that is your personal computer they have every right to check the computer.
What you have asked is in reality a compound question. It is comprised of two independent segments, each of which is a question in its own right.
Answer to Segment #1: No.
Answer to Segment #2: Yes.
Emails sent from school or business computers are generally not considered private as the institution owns the hardware and has the right to monitor communications. Users should be aware that they have no reasonable expectation of privacy when using these systems. It is advisable to refrain from discussing sensitive information over these channels.
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