Help! Email problem

I keep getting this message and I cannot send mail to most people. This just started happening. Any solutions?

The message could not be sent because one of the recipients was rejected by the server. The rejected e-mail address was ''. Subject 'Fw: ', Account: 'pop', Server: 'mail', Protocol: SMTP, Server Response: '473 relaying prohibited. You should authenticate first', Port: 25, Secure(SSL): No, Server Error: 473, Error Number: 0x800CCC79

Edited to hide the email address

Sounds like your outgoing server(SMTP) settings are incorrect.

It means you're using a smtp server that is not on the same domain as you are. They probably just set it up like that recently to prevent spammers from using the server.

Usually they will set up some other way for legitimate users to connect remotely, where some kind of encryption is required, and you are required to log in with a username/password. For example at UMass when you're on the campus network you can use without logging in, on port 25(regular smtp), but if you are offcampus you use on port 465(secure smtp) and you have to provide a name and password.

All that makes sense. I am a home user and use a cable connection and have not done anything to it. Do I contact the cable company or is this somthing I can do from my pc? thanks for all the input.

You should be able to set it up from your PC, but you need to contact them to find out what settings to change.

Thanks for the help. I got it fixed after I called the cable company. Some setting was off as suggested. Thanks again.