550 5.7.1 Relaying not allowed:

[Dave Neve]

Hello

I have started to get the above error which I understand but....I am not
relaying.

I think it may be a server problem but I am checking all possibilities just
in case.

The two emails concerned were both sent out using the 'answer button'.

I have checked the senders address which was as expected (me at my ISP)
thinking I may have had a virus and I have also checked my connection to
make sure a dialer hadn't changed my connection.

I have an anti-virus and firewall as well and they are both up to date .

I have never had a second account either on this computer.

So the question is

'Is there anything in Outlook that could have got changed to cause this
error?'

Thanks

 

[Vanguard]

Hello

I have started to get the above error which I understand but....I am not
relaying.

<snip>

Authenticate to your SMTP server. Off-domain port 25 (SMTP) traffic blocked
to thwart spam from spamming or infected customers. See:

http://www.commercestreet.com/Blocking_Port_25.htm
http://help.yahoo.com/help/us/mail/pop/pop-38.html

http://www.postcastserver.com/help/Port_25_Blocking.aspx
http://www.aota.net/Troubleshooting/port25.php4
http://www.spamhaus.org/faq/answers.lasso?section=ISP Spam Issues#133
http://www.findarticles.com/p/articles/mi_zdewk/is_200406/ai_ziff129473

http://www.google.com/search?q=+block++"port+25"++SMTP++spam