If you are getting a MIME-type related error while sending email from Yahoo to a JodoHost hosted domain, then you need to allow such a MIME type for the domain.
Error message:- Remote host said: 554 sorry, the text/html mime type of the message is in the list of denied for delivering (#5.6.0) [BODY]
Solution:- Allow the text/HTML MIME type in your antivirus program (in the mail manager section in the H-Sphere control panel)
Help Guide:- http://www.psoft.net/HSdocumentation/user/antivirus.html#mailbox
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