I have installed the KB 976323 security update on my Sharepoint 2007 servers but now find that my Incoming E-Mail to sharepoint lists no longer gets delivered. I get an NDR stating servername.domain.com #550 5.7.1 Unable to relay for emailaddress@emaildomain ## . I have tried changing configuration on Sharepoint Incoming Email to not enabled and then re-enabled in the hope that settings would be reset but still the same problem. I have also tried removing the security update but still have the same issue. I have also tried disabling incoming email settings, removing SMTP service, removing patch and then re-adding everything with no luck.

Hi Debbi, Have you checked the settings of your SMTP server what are the relay restrictions? To configure the SMTP service 1. Verify that you have the following administrative credentials: a. You must be a member of the Administrators group on the local computer. 2. Click Start, point to Administrative Tools, and then click Internet Information Services (IIS) 6.0 Manager. 3. In IIS Manager, expand the server name that contains the SMTP server that you want to configure. 4. Right-click the SMTP virtual server that you want to configure, and then click Start. 5. Right-click the SMTP virtual server that you want to configure, and then click Properties. 6. On the Access tab, in the Access control area, click Authentication. 7. In the Authentication dialog box, verify that Anonymous access is selected. 8. Click OK. 9. On the Access tab, in the Relay restrictions area, click Relay. 10. To enable relaying from any server, click All except the list below. 11. To accept relaying from one or more specific servers, follow these steps: a. Click Only the list below. b. Click Add, and then add servers one at a time by IP address, or in groups by using a subnet or domain. c. Click OK to close the Computer dialog box. 12. Click OK to close the Relay Restrictions dialog box. 13. Click OK to close the Properties dialog box. Reference http://technet.microsoft.com/en-us/library/cc287879.aspx -IvanIvan Sanders My LinkedIn Profile, My Blog, @iasanders.