CSE 2.5.0.27 w/ Outlook 2003 and Outlook Connector for Hotmail

Using CSE 2.5.0.27 w/Outlook 2003 and Outlook Connector MAPI. When sending email get CSE popup error that says
“The mail can not be processed. Error: The parameter is incorrect. Would you like to send the mail unsigned and unencrypted? y/n.”

Please help me determine cause and resolution of problem?

Thanks