What is the point of these bogus 'FedEx' messages

I’ve gotten maybe three supposed messages in my e-mail from ‘FedEx’ with a tracking number, saying they couldn’t deliver, I should print out this receipt and go to the nearest office to pick up my shipment. ? All of this is horse puckey. What are these things, who are they from, and what are they trying to do here?

Oh it’s a delivery all right, malware delivered right to your computer.

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