html formatting in signature and email body not working

The html formatting in my signature and email body does not work when an email is sent to anyone not on my company outlook exchange server.  It appears to convert the signature to simple text even though mail format is selected as html for new messages and replies.  In addition, any formatting done in the message body also gets converted/messed up.  Any idea why?

Hello Jeffrey,

If your eM Client’s settings look the way that you describe, than we would recommend checking the settings on the server. This issue could also be caused by the settings on the receiver’s server or the program they use to view the messages. If you’d like, you can send us an example of a message from somebody who sees the reply in the simple text exported as .eml to hester@emclient.com with a link to this thread.

Regards,
Maurice