Hi All, I'm usually quite good with sendmail on Centos 5.8 but I must have missed something here. I've not done this before but, I want to set sendmail so that its outgoing mail appears to come from the domain of the network it lives on. Its real hostname is server2.domain.co.uk ( the domain bit is substituted for this post) and I want it to send as domain.co.uk, that is really valid, but the specific host server2.domain.co.uk does not have an A record and other mailservers reject its outgoing mail because server2.domain.co.uk does not resolve. But with these settings in sendmail.mc it still sends as server2.domain.co.uk if I simply type "mail -s test kens at kensnet.org" into bash. MASQUERADE_AS(`domain.co.uk')dnl FEATURE(masquerade_envelope)dnl FEATURE(masquerade_entire_domain)dnl MASQUERADE_DOMAIN(domain.co.uk)dnl (Yes I have done the m4 bit and restarted sendmail) If I telnet to sendmail on port 25 and manually send as username at domain.co.uk it has the right "from" address. So what have I missed? Thanks Ken -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.