Pop open an HTML mail you have on your system and view the source. It's likely you want to create a "multipart" email, with one part html/text and the other text. Googling how to create a multipart email should set you on the right track.
On Fri, Oct 14, 2016 at 4:57 AM, Alan Bourke alanpbourke@fastmail.fm wrote:
Programmatically?
Are you sending a content type in the header?
Content-Type: text/html; charset=UTF-8
Also you should construct both a HTML and plain text version of the mail and send both with the appropriate headers as not all mail clients will accept HTML messages.
-- Alan Bourke alanpbourke (at) fastmail (dot) fm
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