I have recently experimented with a service that tracks emails. My experimentation has opened more questions than I have the technical expertise to answer, so I would like some help. Most emails I send are opened once by the intended receiver of the email. Some emails are opened, then forwarded to a second location and opened, and them forwarded to a unidentifiable server and opened a third time.
Is there a logical explanation for this or am I being someone attempting to create a new conspiracy theory? I welcome your suggestions and possible explanations.