I have a customer who has 18 emails on their domain.  They receive emails from a particular domain that is not hosted on my SM instance that sends them in an html format.  This same email is sent to 5 users of the 18 users.

 

Of the 5 users, only one user is not receiving them as html format, but as text instead.  I have checked all the settings for the user and things are set properly.  If I send this user an email that is formatted from my email or another email that isn't on my SM server it comes through fine.

 

I have even deleted the email account and re-created and no luck.  I did create a new user formatted differently (instead of using for example jhop@domain.com, I used justin.hop@domain.com). Since doing so, the newly created user receives emails in html for outside domain mentioned in the beginning.