c# - Write MIME file with double-quotes -

I am manually building a multi-part MIME-formatted file and am submitting it into the SMTP pickup directory . When email arrives in my inbox, it has lost double quotes of any double-coat words. E.g.

  & lt; Html lang = "eng" & gt;  

becomes

SMTP (Power Mta) has been presented and contains all the correct double quotes etc.

What is happening here And how do I code around it? My end user is HTML-based outbound email, so he has to face any HTML content.

This is not about <, about it = about = > = 3d to Should Rthyt. There are also other limitations that you can find inside.