Cannot send E-Mail on OE 6

I have three e-mail accounts set up in Outlook Express 6, in XP Home. I can receive mail on all three accounts, but I can only send e-mail on one account, the address supplied by my cable internet provider (Charter.net). The other two accounts are from a dial up provider and a subscribed bullitin board. When I try to send from the latter two, I get the following error message:

The message could not be sent because one of the recipients was rejected by the server. The rejected e-mail address was xxxx. Subject xxxx. Account 'mail.xxxx.com' Protocal SMPT, Server Response: 503 This mail server requires authentication. Please check your mail client settings. Port 25, Secure (SSL): No, Server Error: 503, Error Number: 0x800CCC79

Does anyone have an idea or suggestion as to what to do about this problem? This has been going on for quite a while, so it's not something that just happened. As far as I know, it might have been going on since I first set up the accounts and just never noticed it.

Thanks in advance.

 

In tools, options, mail tab, properties of the 2 accounts that won't send. What ever server you use(the one that's working to send), you need to have the outgoing mail server info the same as the good one. That is a design feature to prevent spammers from routing through other servers.

 

That worked! Thanks very much!

 

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