sending mail

So I can receive mail just fine but when it comes to sending mail it says "the username or password is incorrect" this doesnt really make sense because I can receive mail so how can my user name or password be incorrect?

Depending on how your email is set up the password and username to send may be different to send than to receive.

For example, to receive mine only requires my account username & password. To send it requires the master account username and password. This is true for all of the e-mail accounts on my home POP e-mail server. My MobileMe IMAP e-mail doesn't do this.

thats weird...I don't remember setting anything like that...anyways how do i fix it??

EDIT: Beauty I just fixed it. I went to my settings and added a password to the outgoing mail server (apparently there wasnt one)