My Exchange server is getting attacked and I cant tell where the emails are coming from. When I go to my server and look under Queues, there is a long list of emails trying to get out. They're spam, because there from bogus email addresses. When I look under the properties of one of these emails, there's no way of telling me where these emails are coming from. Most of the senders are: "PayPal"<email@example.com> Obviously one of my computers is infected or I'm being hacked. Is there an easy way of figuring out where they are coming from? I tried Wireshark, but I'm new to it and it's hard to understand it. I tried filtering SMTP, but I couldn't pinpoint where the messages were coming from. Thank you in advance.