I have always used a valid "from" field, even the log4j book I have is silent as to if the "from" address needs to be valid. You don't have to add the extra category - what you did earlier for root should be fine. The one thing I don't see for the SMTPAppender is authentication handling. I know that my ISP requires an account and a password to send email. But I cannot recall how I handled this when I set up the SMTPAppender before (and of course I no longer have that configuration). OK, I looked up the javadoc for SMTPAppender (http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/net/SMTPAppe...), there is a SMTPUsername and SMTPPassword parameter, which you can set using: <appender ...> | ... | <param name="SMTPUsername" value="xxx"/> | <param name="SMTPPassword" value="xxx"/> | </appender> The stupid book I have doesn't event mention these parameters, nor a few others that are available on SMTPAppender. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4263757#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...