If you want to know the ip address of email sender and the ISP that is used you can read the following tips.
Yahoo Mail:
Login to Yahoo Mail.
Choose one that you want to check email.
Click on the menu or Full Header link located at bottom right.
Locate the “Received: from [...] by”.
In the example below is the IP address 61.94.152.147.
MS Outlook Express:
Open the Outlook Express program
Right click on one of the emails that you want to check.
Click the Properties menu.
Click the Details tab.
