If you receive an email from the “Mail Delivery Subsystem <email@example.com>”, then a message that you had sent has bounced back to you for the specific reason that is reported on the “Mail Delivery Subsystem” message. In other words every email that comes from the “Mail Delivery Subsystem” is created automatically and contains the reason for the message delivery failure.
However what if you’re receiving Mail Delivery Failure notices for messages you are sure you did not send? When this happens you can receive dozens, hundreds or in extreme cases even thousands of these. When this happens, generally there may be two causes:
1. Your computer has been infected by a virus that is sending emails from your address without your knowledge.
2. A spammer is forging your email address for the spam they’re generating. Email addresses are forged in order to disguise the actual origin of the message. In almost all cases of forgery, the message is sent from a different location and not from your email account and/or email service.
In both these cases, the messages are sent to random email addresses, that are placed in the To:, Cc:, or Bcc: fields. If the recipient email address happens to be valid, they’ll receive the spam/ email fraud. However, if the recipient email address is invalid, you’ll receive a Mail Delivery Failure notification.
If you receive a Mail Deliver Failure notice but have not sent any messages, you should take the following steps to protect your computer and secure your account.
1. Immediately change your account password. If you are a Big Grizzly client - our password standards can be viewed under paragraph 14 of our terms and conditions. Use a password that is easy for you to remember but difficult for other people to guess. Avoid using birthdays or children’s names, and instead think of a line from an old movie or song and use the first letter of each word. Use both letter and number combinations with at least 6 characters.
2. Run a Virus Scan and remove any infections. Make sure that you have installed the latest updates for your anti-virus program, then run a complete system scan to identify and remove any virus or malicious program. If you do not have an anti-virus program on you computer, we at Big Grizzly recommend McAfee, but there are lots of good options available.
If you have are receiving Mail Deliver Failures because a Spammer is spoofing your email address, after taking the above steps there is, unfortunately, little else you can do. Eventually the spammer will move on to other email addresses. You can set an email filter to move these to spam (or ask you email provider to do so) but the risk here is that you will miss legitimate delivery failures also.
There are not always good options here, just make sure your email account and computer are secure. These are not uncommon but the can certainly be a headache.