Question : Outlook Express response: 550 5.7.1 Authentication Required

Using Outlook Express from a laptop via DSL, outgoing mail is now stopped with the following pop-up window Command sent was: "MAIL FROM < my email address>  Response received : 550 5.7.1 Authentication Required".

Email in Outlook has been verified as to the proper POP3 settings, etc.  Can send ok via Hotmail.  Also sending ok via another computer on the network which uses Outlook Express.  

Thanks

Answer : Outlook Express response: 550 5.7.1 Authentication Required

The short answer is in you outlook express account properties select my server requires authentication (Server Tab)  that should solve your problem.