When attempting to send emails to attg.net or attglobal.net, our workers receive error messages such as the following:
"Your message did not reach some or all of the intended recipients ... The following recipient could not be reached: 'user@attg.net' ... The recipient was unable to take delivery of the message ... 550 unauthorized interface for (our IP address) on in9."
Does anyone know what causes this type of error and what can be done to enable our messages to reach users @attg.net??
Thank you for any answers.
"Your message did not reach some or all of the intended recipients ... The following recipient could not be reached: 'user@attg.net' ... The recipient was unable to take delivery of the message ... 550 unauthorized interface for (our IP address) on in9."
Does anyone know what causes this type of error and what can be done to enable our messages to reach users @attg.net??
Thank you for any answers.