"Alby" wrote:

I have exactly the same problem. Same text message, same error message but
the authenication box IS checked. Any clues what to try next ?

>
>
> "Gary VanderMolen" wrote:
>
> > You're very welcome. Thanks for reporting back.
> >
> > --
> > Gary VanderMolen, MS-MVP (Mail)
> >
> >
> > "Trish58" <Trish58@discussions.microsoft.com> wrote in message news03C053E-F79B-476E-BA4F-B81EF6693C0A@microsoft.com...
> > > that's great. I've been struggling for days and you sort it out instantly -
> > > brilliant - thank you so much
> > >
> > > "Gary VanderMolen" wrote:
> > >
> > >> Like it says, you need to use SMTP authentication:
> > >> Go to Tools, Accounts, select that account, Properties, Servers.
> > >> The box for "My server requires authentication" must be checked.
> > >>
> > >> --
> > >> Gary VanderMolen, MS-MVP (Mail)
> > >>
> > >>
> > >> "Trish58" <Trish58@discussions.microsoft.com> wrote in message news:EA2F48B9-C5C8-4281-AF31-5C660305CE20@microsoft.com...
> > >> > for several days I have been unable to send email though can receive ok.
> > >> > this error message appears:
> > >> > The message could not be sent. The authentication setting might not be
> > >> > correct for your outgoing e-mail [SMTP] server. For help solving this
> > >> > problem, go to Help, search for "Troubleshoot Windows Mail", and read the
> > >> > "I'm having problems sending e-mail" section. If you need help determining
> > >> > the proper server settings, please contact your e-mail service provider.
> > >> >
> > >> > The rejected e-mail address was 'godeans@gofast.co.uk'. Subject 'youtube',
> > >> > Account: 'mail.o2.co.uk', Server: 'smtp.o2.co.uk', Protocol: SMTP, Server
> > >> > Response: '550 RCPT TO:<godeans@gofast.co.uk> Relaying not allowed - please
> > >> > use SMTP AUTH', Port: 25, Secure(SSL): No, Server Error: 550, Error Number:
> > >> > 0x800CCC79
> > >> >
> > >> > please can anyone help??
> > >>
> >