The problem does not appear to be your end, rather the addresses your users are trying to send e-mail to. Check the address, you will probably find invalid characters in the area you have "blanked" out. for example.. [steve@gateway steve]$ telnet mail.letsos.com 25 Trying 68.164.127.90... Connected to mail.letsos.com. Escape character is '^]'. 220 mail.letsos.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.0 ready at Sat, 3 Jan 2004 21:00:30 -0600 HELO focb.co.nz 250 mail.letsos.com Hello [210.48.7.253] MAIL FROM: <test@xxxxxxxxxx> 250 2.1.0 test@xxxxxxxxxxxxxxxxxxxx OK RCPT TO: <fr<ed@xxxxxxxxxx> 501 5.5.4 Invalid Address The clue is the bounce message - they are not telling fibs. If it says "oh yeah, this address <*****@letsos.com> is invalid" then it simply is - at times this can be an extra dot, a space or other hard to spot things, but it _will_ be invalid. (a classic is a trailing space in the domain name :-) ) Also, keep in mind - this message was generated by the far end mail server - this means that your users sent mail through a server, the server (not necessarily your one) tried to deliver it, the letsos server said "no, bog off, this is invalid" and the sending server said "darn !" and generateda message to send to your-user@xxxxxxxxxxxxxx to tell them that the e-mail address they just tried to send to was not valid. most of this can be completely independant of your mail server (a trick spammers like to take advantage of) and as long as your mail server is working ok your user will get the bounce, if your mail server is not working they wont get a bounce. Things look fine for your mail system as far as I can see and this looks like a PEBKAC error. -- Steve. > I have setup a sendmail server and have been using it successfully for a > week or so now. I added some more accounts and these people and been > complaining of having some of their emails returned to them with the > following error: > > ------------------------------------------------------------------------ > > ----- The following addresses had permanent fatal errors ----- > <*****@letsos.com> > (reason: 501 5.5.4 Invalid Address) > > ----- Transcript of session follows ----- > ... while talking to mail.letsos.com.: >>>> HELO mail.frazerbilt.com. > <<< 501 5.5.4 Invalid Address > 554 5.0.0 Service unavailable > > --------------------[ here is the details.txt file: > ]-------------------- > > Reporting-MTA: dns; mail.frazerbilt.com. > Received-From-MTA: DNS; adsl-65-66-208-5.dsl.hstntx.swbell.net > Arrival-Date: Thu, 1 Jan 2004 09:45:24 -0600 > > Final-Recipient: RFC822; *****letsos.com > Action: failed > Status: 5.5.0 > Diagnostic-Code: SMTP; 501 5.5.4 Invalid Address > Last-Attempt-Date: Thu, 1 Jan 2004 09:45:25 -0600 > > ------------------------------------------------------------------------ > > The * is to hide the real email address. > > I thought it might have something to do with the reverse lookup of my > mail servers name, but I checked and it is correctly mapped to > mail.frazerbilt.com. > > My servers IP address is 65.45.50.130. > > Can anyone tell me what exactly that error message means? > > Thanks > > -- > redhat-list mailing list > unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe > https://www.redhat.com/mailman/listinfo/redhat-list > > > > -- > redhat-list mailing list > unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe > https://www.redhat.com/mailman/listinfo/redhat-list > -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list