"Well received" isn't really used when writing emails. Usually, information that we give to some is well-received when they accept it. For example: I told my friend he should get a haircut because it might help him find a job. I thought he might get angry, but the it was well-received. and: The suggestion to my manager that we should reduce spending on equipment was well-received.

Hi Lydia! It means that he/she has surely received your email. 😊

Well received means something has gotten a good reaction or has been views with approval. Well received 的意思应该是某件事情获得良好的反应， 如果在收邮件这个情况下，回复well received，就有点像是说这封邮件写得很好或者是这包含了很好的想法。想要更多的建议。我认为这有点不太合适的。 如果想表达收到电邮，可以说： Thank you for your email. Received with thanks. Well noted.

Yes, as others have said, its not really supposed to be used in emails. It's something you say when you tell person C that person B pleasantly acknowledged your news, or made you feel welcome