If you’re receiving error messages from the mail delivery subsystem, it may be a sign of a hacker’s activity. The email server will repeatedly attempt to deliver a message for a certain period of time before returning it with an error report. If you’re receiving error messages more than once a day, it could mean that your email account has been hacked. These messages may also come even if you haven’t sent any messages. In some cases, the total number of error reports sent by the mail delivery subsystem may exceed thousands of emails.
Messages from mail delivery subsystem are not spam
You can check if an email is spam by looking at its source. The first “received” line in the header indicates the email’s source. If the IP address of the sender is outside your network, the email is probably not spam. If it is, you should change your password and check the machine for malware.
How to stop receiving mailer-daemon emails
If you’ve recently noticed an unusual number of mails arriving on your computer, you may have been receiving “mailer-daemon” emails. These emails are triggered by a problem with your email server or with your e-mail address. When you receive these messages, you should check them carefully before responding. Sometimes, the messages could contain viruses.
To block mailer-daemon emails, use your email provider’s settings to block their addresses. This is especially important if you receive notices that seem to be scams. However, before doing this, you need to verify the address of the person receiving the emails.
You can also check your bounce messages. This will let you know if the email address is indeed a spammer’s. If you have a compromised password, this could also be the reason for the bounce. While it may be a nuisance, it will give you some insight into the origin of the messages. Often, these messages contain spelling mistakes and information about the recipient’s email address.