All email messages contain Internet headers full of important information about the sender and the path the message took as it crossed mail servers before ending up in your inbox. There are two types of headers in Yahoo emails: the brief header and the full header.
Although an attacker can include forged information in the brief header and make a suspicious email look legitimate, he can't forge the full header. You can get the IP address of the sender in Yahoo Mail by looking at an email's full header.
If an attacker uses a proxy server, the IP address you get from the header is not his real IP address. Experienced hackers use several proxies, making it very difficult -- but not impossible -- to find their location.
Log in to Yahoo Mail, select Inbox from the left pane to view all received emails and then click the suspicious email to open it.
Click More and select View Full Header from the menu to display the Full Header box, which contains the IP address of the sender, among other useful information about the message.
Scroll down using the right scroll bar until you find the X-Originating-IP line to find the IP address of the sender.
- You can select the IP address -- or everything -- in the Full Header box and then copy it to the clipboard by pressing Ctrl-C. To select everything, press Ctrl-A.
- You can't delete information from the header in Yahoo Mail.
- You can use a free online service to attempt to trace the IP address. Don't rely entirely on a tracking service to find the location of the sender.
- All major email services -- Gmail, AOL, Yahoo and Hotmail -- allow you to view the full header of an email. Email clients such as Microsoft Outlook are also able to display full headers.