Changing email address within web site

I believe I have come under cyber attack and as a result emails sent automatically from my site to hotmail or live.com are being blocked. Here is the message I get:

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  ando1955@live.com.au
    SMTP error from remote mail server after MAIL FROM:<admin@bisexualaustralia.com>
SIZE=1829:
    host mx1.hotmail.com [65.55.92.152]: 550 SC-001 (SNT0-MC2-F39) Unfortunately,
messages from 184.154.183.249 weren't sent. Please contact your Internet service
provider since part of their network is on our block list. You can also refer
your provider to http://mail.live.com/mail/troubleshooting.aspx#errors.

When I check the troubleshooting area I discover that 550 SC-001 means I'm suspected of spamming. The only way I can see out of this is to change the email address linked to my web site but I don't know where it is buried. Thanks.

Hello

You need to contact with your hosting provider. May be your site sent too may mails (using for example mass mailer) and was blocked.

You will probably have to file an appeal with Hotmail and ask to be un-blocked.

Just what is a "cyber attack"?

You can change your email all you want, but will not change anything.

Their blocking is based on your IP address.

Worth noting - if a competitor can do this to me, there's a good chance malcontents could do it to any Boonex web site. Anyone could end up on Hotmail's black list.

msscott - any idea how I would go about lodging an appeal with Hotmail?

I can email my Hotmail subscribers from an alternative email address I have via the same host, and I can email my Hotmail subscribers from a Yahoo email address. I think this proves that it isn't my IP address that is being blocked, nor my ISP, nor my web host. 

The problem is with the email address that is linked to my web site.

If I knew how to change that I think my problem would be solved.

So whereabouts on a Boonex Dolphin web site is it located?

Thanks.

Admin->Settings->Basic Settings is where you change the site email address. On older versions of dolphin they are in inc/header.inc.php

However the fact that you can email them from a different email address does not prove your IP is not blocked. Your server will send the email itself, thus they are coming from the IP address of your server not the server your host uses for your alternate email. So it still does not prove it's not a blocked IP.

Newer versions of dolphin have a SMTP mailer module. Properly setup your mail could be sent out through your hosts mail server instead of yours.