What is an email header?
Each email you receive comes with headers. The headers contain information about the routing of the email and the originating IP of the email. Not all emails you receive can be traced back to the originating point and depending on how you send emails determines whether or not they can trace the email back to you. The headers don't contain any personal information. At most, you can get the originating IP and the computer name that sent the email. The originating IP can be looked up to determine from where the email was sent. IP address location information DOES NOT contain your street address or phone number. It will most likely determine the city and the ISP the sender used.
How do I get the email header?
Each email program will vary as to how you get to the email options. I'll cover the basics...the rest is up to you.
- Outlook
Right click the email while it's in the inbox and choose Message Options. A window will open with the headers in the bottom of the window.
- Windows Live Mail
Right click the email while it's in the inbox, choose Properties, then click the Details tab.
- GMail
Open the email. In the upper right corner of the email you'll see the word Reply with a little down arrow to the right. Click the down arrow and choose Show Original.
- Hotmail
Right click the email in the inbox and choose View Message Source.
- Yahoo!
Right click the email in the inbox and choose View Full Headers.
You can see that no matter the email program, the headers are usually just a right click away.
I've got the header, now what?
Usually the first IP listed is where the email originated. There are exceptions to this. You'll have to look at the information logically to deduce the originating IP.
Can any email be traced?
Yes and No. For example, someone who sends an email to your hotmail account shows in the X-Originating IP section of the headers. However, someone who sends you an email from GMail can ONLY be traced back to the GMail servers.
- JMD COMPUTER INDIA
Source: http://www.whatismyip.com/faq/how-to-trace-an-email.asp