Hi Fan

Sorry I didn't spot your posts earlier. I'm a computer professional by trade and your problem sounds like your e-mail server, or that of your internet service provider, has been added to one or more RBL black lists. This happens when other mail servers complain about spam coming from another mail server. This is not necessarily your fault. I don't know your network situation, but it could be that another p/c on your ( or your ISP's ) network has been infected and is sending out spam, or there could other causes.

Many mail servers on the internet are set up to refuse e-mail from any server on a black list. I can tell you from experience that it cuts down on spam a lot. You should examine any refused e-mail you send to ECU. They are usually returned with an explanation stating that your server is on an RBL black list. If you see anything like that you should contact your ( or your ISP's ) mail administrator immediately. Your admin will want to get off the black list asap as other's e-mail will be blocked as well.

Hope this helps