"SMTP 550 error, 5.1.1 User Unknown"

**2muchreality** · 18-04-2008

I am running SBS 2003 with SP2. I have restored our server yesterday and got everyone up. After that I went to my pc to get it online and noticed that I am not getting emails. I can send fine, but incoming is getting the 550 error. Exchange 2003 SP2 was installed from the CD's with SBS and all I have changed is to uncheck NDR's and set it up for my Custom DNS service through DynDNS.org. There is also nothing new in the Application or System logs. Can anyone help? Thanks

**2muchreality** · 18-04-2008

I also wanted to add that in CEICW I have set the domain to "whoopingcrane.org" and the mail to "mail.whoopingcrane.org".

**2muchreality** · 18-04-2008

I have solved the problem now, I actually had my email address setup wrong in Server Manager, left out the "underscore" in my name.

**Tomthegreat** · 22-04-2008

If the problem still persists, then follow the below link and make sure you restore the SBS through the recommend steps:

http://technet.microsoft.com/en-us/l...6-327166ef3e90