The internet header holds confidential information such as the sender, the email server etc. Most time we do not need that, but if you want to check the internet header for a message, please follow the steps below:
Step 1: Double-click the message to have it open in a separate window;
Step 2: Click the "File" tab in the ribbon;
Step 3: In the new window, click "Properties";
Step 4: At the bottom of the new window, you will find the internet header.