Mail From Error appears when sending addresser's information to the object
server. The reason is it is rejected by the object server, the addresser' s
mail address has been put into the black list or the network error etc. This can be confirmed after the object server has reaction.

Send data error shows when sending mail text to the object server. It
probably happens because of the excess size of mail text, the inner error of object server or the breakup network when tranfer. It can be checked till
the server has feedback as well.

Connection Fail means wrongly connected to the object server, which appears before sending messages to the object server. Network error, local IP has been put into the black list or the object server is off line etc can creat
such error.