Internal mail server IP in header Share on Facebook Post on reddit Tweet on Twitter Share on LinkedIn Home › Forums › Messaging Software › Exchange 2000 / 2003 › Internal mail server IP in header This topic has 4 replies, 2 voices, and was last updated 12 years, 11 months ago by ronroze. Viewing 1 post (of 1 total) Author Posts ronrozeMember Oct 18, 2007 at 3:11 am #128332 Hi guys, I have just received an NDR for an email I sent, which says: 550 5.7.1 This system has been configured to reject your mail. An IP address (100.100.100.1 – our internal mail server’s IP ) found in the message’s ‘Received:’ headers is listed by the lookup site. Is there a way to hide our server’s internal IP (both for security reasons and for preventing cases like this one?) thanks… Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic.