This occur only wiht some domains. When I send an mail for some domains, this message stayed in Queue Viewer and after some time I can see this error. (Last Error: 450 4.5.0 No recipient succeeded) or: (Last Error: 400 4.4.7 Message delayed). What I did was to solve: 1 - In my ISP the DNS reverse it's OK. 2 - In internal server DNS, I have a forwarder that is able to resolve external address. 3 - I'm not using smart host. for example: Server: domain.empresa.local Address: 192.168.0.8 Non-authoritative answer: cidades.gov.br MX preference = 5, mail exchanger = belem.cidades.gov.br belem.cidades.gov.br internet address = 200.198.212.130 This is a test using nslookup in my exchange server. What can it be? regards, Letícia

I don't know what happen, but the email was recieved after some hours and I dont did changed anything, but I have another problem with bradescoseguros.com.br domain, the error is: Last Error: 400 4.4.7 Message delayed What can it be? regards, Letícia

Hello Leticia6, [Another problem with bradescoseguros.com.br domain, the error is: Last Error: 400 4.4.7 Message delayed] It may be your DNS Server is not able to resolved the MX for bradescoseguros.com.br domain, please check the DNS server and correct it so it can resolve the MX of remote domains. OR it may be problem with remote domain. Please create a didicated SMTP connector for bradescoseguros.com.br with MX as smarthost and the send one test mail & check. It will fix your problem. MicroSoft Exchange Admin. & Connector EXCHANGE2010, MCSE, MCTS, MCSA MESSAGING, CCNA & GNIIT

Hi Leticaia, Any update for your issue? Regards! gavin