This overrides the automatically-set MIME content type of the message body. It does not affect any other part of the message. Examples: "text/plain" and "text/html".
This is a more advanced parameter. You can use this parameter in situations when you have some specially encoded content that you want to "inject" into the message sent by NetMailBot, and you want it to show up in the email client a certain way (i.e. as a certain mimetype), for example, "application/msword".
Other Parameters Required:
-mimetype "<mime type specification>"
Example (cut-and-paste right into your batch file):
NetMailBot -mimetype "text/html" -body "plain text body" -to firstname.lastname@example.org -from email@example.com -server mail.domain.com -subject "test"
Using -htmlbody is functionally equivalent to using -mimetype "text/html" as in the above example.