Naturally occurring files can share hash values

Yes, they can. It's called a hash collision.

I’ve tried and doesn’t let me either

Once the twisted pair cable is connected and a network is established the led lights at the back of the computer should be steady. on most ethernet adapters nowadays, a steady green light means that the connection is actively connected to a valid partner at the opposite end. if the status of the led starts flashing, this means that there’s some activity and data is being transferred.