Can I know Email client sender IP?

Is there away to know original email sender IP, I mean the client machine which is used to send the email not the smtp sever. 开发者_如何学编程

where in the header if any?

The address will be in the last Received: header in the message headers.

Note, that if the user used some proxy (SOCKS or HTTPS), you'll see proxy's IP. Also the record can be forged by putting fake Received: headers to the bottom and making it look like the sender is just a resender.

Sometimes it's included in the headers, but more often than not it is not.

So fortunately, no, there is no reliable way to tell the email sender's IP if it's not in the headers. I imagine it would be a big privacy issue if that wasn't the case.