Answers

Q Unauthorised address

I have installed CentOS 7 in VirtualBox. I tried to send an mail using the mail command like this:

But I get this error message:

The IP you’re using to send email is not authorized......

I tried clearing the IP mentioned in the above error logs from SPAMHAUS and no luck. What could be reason I am not able to send email from my Linux server to any external email account? What is needed to get this resolved?

Julie Pirouet

The mail command needs an SMTP server in order to send mail. If you haven’t specified one on the command line, I will assume you are using running locally, as that is the default configuration of CentOS. So mail (the command) sends your email to , which then determines how to send the email to the recipient and tries to do so. The last part is causing the problem and is most likely because you are using a residential IP address. Many servers reject mail coming from residential IP addresses because they are often spam from a compromised Windows system. The answer is to send your email through your ISP’s mail server, which is trusted by the rest of