Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

Maddy — Sat, 19 Jan 2013 15:53:40 GMT

I was trying to fix this problem since long back. Thank for the solution.

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

Caique — Tue, 26 Jun 2012 02:16:22 GMT

Thank you, you solved my problem ...

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

Jenny — Wed, 28 Mar 2012 05:50:13 GMT

Here is detailed post about the error 550 and its resolve.

exchange.stellarservertools.com/.../troubleshooting-exchange-error-550-unable-to-relay

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

David Alban — Wed, 24 Aug 2011 15:24:36 GMT

If you are using the pickup directory on a Windows Server 2008, and nothing sends, try turning off UAC (User Account Control). That worked for us.

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

danielgc — Wed, 25 Jun 2008 20:19:50 GMT

thx for sharing the solution, it worked for me

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

mheryer — Tue, 15 Apr 2008 23:32:23 GMT

Hello,

I have the same problem with a single domain name that my users and servers seem to be sharing: the inablility to send to a specific domain. We get 5.7.1. Unable to relay ... or NDRs stating the address is unroutable. I have tried to telnet test to my servers and get 5.7.1. ... I have tried the configuration described above with no luck. I know it's a valid email address as some of my people can email to the name from external accounts. Any ideas?

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

Natarajan — Sun, 13 Apr 2008 08:04:59 GMT

I have two servers internal and ext(front end and backend).Which server I shud add to the relay list my internal server or my external.

I am working on my internal right now..pls let us know which entry to add

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

Gaurav — Wed, 05 Mar 2008 10:25:58 GMT

Thanks a lot... I have been trying to work on this problem since many many days and never thought the solution will be so simple! Thanks a lot :)

Gaurav

re: Resolving SMTP error 550 5.7.1 Unable to relay for user@domain.com Error 0x800CCC79

Chris Buechler — Fri, 14 Oct 2005 03:56:41 GMT

not only "more secure", it keeps you from being an open relay! Unless you enjoy sending out millions of emails on behalf of spammers, DON'T use the "all except the list below" option.

see: http://en.wikipedia.org/wiki/Open_mail_relay

Of course this isn't of as much concern if TCP 25 (SMTP) on your mail server isn't open to the Internet. I'd still never setup a completely open relay, Internet-accessible or not.