Recently we've had an issue sending email out to one of our divisions when they open a ticket. OSTicket gets the email and opens a ticket, but when we respond to the ticket we receive a bouceback email. This only happens with one particular domain, however. When I log into the email box that the ticketing system uses, I am able to send email to that domain with no problems, but when OSTicket tries to send to them, using the same email address, it won't go through.

The error we're receiving is the following:

host mx.cause*.com[66.xxx.xxx.143]
refused to talk to me: 554 bosimpinc02 bizsmtp Connection rejected.
Reverse DNS for 208.xxx.xxx.180 does not exist.

Every other domain we try to send to works with no problem, it's just this one specific one, and again, if I log into the email account directly, there is no issue with sending email.

Thanks!

Joe