I have had a few discussions with people recently as to why they haven’t been able to recieve emails from genuine senders when the sent email is bounced back. Was it a problem with the receiving email server or is it an issue with the sender?
This is a question that seems to pop up from time to time. When an email is bounced normally people will assume that it is the recipient who is at fault but in reality this may not be the case.
Having investigated this a little I have discovered that the majority of cases where legitimate email has been bounced is due to the email being sent via a free email service such as hotmail, yahoo or gmail.
The reason why email tends to be bounced is because the recipient mail server will be using one or more blacklists including http://www.ordb.org, http://relays.osirusoft.com/ or http://spamcop.net/bl.shtml?. When an email is sent via a server listed in one of these blacklists, the recipient server will automatically bounce any email with a matching ip address.
How does a mail server get listed? It tends to happen when a mail server is repeatedly flagged as sending spam. If that server is known as one responsible for delivering spam then it will automatically be bounced from any recipient server.
What can I do to get my email through? If you absolutely must use a free email service like gmail then have an account set up for it in your email software but make sure you use your ISP’s SMTP server. Failing that, if your email is being bounced and you’re actually already using your ISP’s SMTP server then it might be time to change service providers. If your ISP hasn’t made sufficient effort to prevent spam being sent via it’s servers then you should be worried about what else they are neglecting security wise.
ISP’s can get delisted once they have proved to the organisation to which their IP address have been blacklisted that they no longer enable spammers to relay their spam through them. Normally there is a small fee involved which is more of a nusiance to ISP’s than anything and in the case with some, they prefer to blame the recipient server than address their own problems.
Just remember to always use your ISP’s SMTP server when you are sending email to ensure your important emails aren’t disappearing into cyberspace.