As email is sent from a mail server and received at the far end and as it travels towards its ultimate email server destination, possibly via other mail servers – a history is built up of its travels in the email header. This email header can be copied and pasted into a mail header analyzer to make is easier to decipher. The analysis will help show route and timings.
Use the following two website’s utilities to analyse an email header:
Both of these websites have other good utilities that might be worth taking a note of for a rainy day.
If you are not sure how to get access to your email’s mail header – then use the mxtoolbox’s handy tutorials: http://mxtoolbox.com/Public/Content/EmailHeaders/