How to collect message header?

Trace an email with its full header

For an email you received in Gmail, you can see where the email came from by looking at its header, including how it got from the sender to the recipient's mail servers.

View your email's full Header

For Gmail

1. Open Gmail.
2. Open the email that you want to check the header for.
3. On the right, next to the reply icon , click the more icon.
4. Then click Show Orginal as shown in the above picture.
   
   
   
   
   
5. The header will show in a new window, including fields like authentication results. To get the full message header, click Download Original.
   
   
   
   
   

For Other Mail Services

Click on Learn more

How to read email full header

1. Open the email you want to check the header for.
2. Next to Reply , click More Show original.
3. Copy the text on the page.
4. Open the Message header tool.
   
   
   
   
   
5. In "Paste email header here," paste your header.
6. Click Analyze the header above.

See if the message is delayed

1. Open the email you want to check the header for.
2. Next to Reply , click More Show original.
3. Next to "Created at," look to see how much time it took for the email to be delivered after it was sent.
   
   
   
   Please check the below-supporting article for your further reference:
   Trace an email with its full headers - Gmail Help