Getting SpamHaus message when testing locally

[antic]

I'm testing a web app on my local PC. It is trying to send an email from server code (ASP on IIS). The SMTP authentication is set up the same as it is when it runs live. That is, SMTP server = mail.mydomain.com, and using an email account and password for auth, using port 587.

It seems to work live, but when I run it locally, it fails to send the email.
The error I get back is this:

The server rejected one or more recipient addresses. The server response was: 451 http://www.spamhaus.org/query/bl?ip=xx.xx.xx.xx

The IP address is that of my local dynamic IP, assigned to me by my ISP. I'm not sure what this means... is it saying I'm not authorised to connect from here to the mail server? Thing is I'm *sure* I've done this before to test emailing.. has anything changed there recently?

 

[Stephen]

It can do that sometimes, in fact sometimes I am on the road and try to send mail on my phone and the tower I am on there is blocked, but another is fine.