Why does the system says that my IP address is blocked even after authenticating to the system?

For every SMTP connection we check the IP address in the spamhaus.org database.

This allows us to reject emails from known spammers.

Even though you are authenticated to the system, the system may still reject mails from you if you IP address is listed in the spamhaus database. This helps us to prevent attacks from systems that have a virus/trojan that uses the information from your email client and send out spam after authentication.

Even though you might have a completely clean computer, you might be blocked because you got an IP address (usually dynamically from your provider) which was in the past used for spamming.

You have two solutions for this problem.

1. To not disturb your work, you can use the webmail which will allow you to send/recieve emails.
2. Inform your ISP and ask them to find a solution.

Your Internet Service Provider provides your mobile device (iphone, Blackberry, Netbook and UMTS-Stick) with an IP Adress. Your ISP charges you for these services and this should allow you to use these services, to their full access. Your ISP is responsible for any action taken from customer side in relation with Spam abuse.

This Q&A was found on Worldsoft Atmail hosted mail service : https://worldsoft-atmail.com/modules/smartfaq/faq.php?location_id=45&faqid=2