We have really struggled to resolve this issue that has been going on for a while now. We get this error intermittently when sending to various outside domains: A configuration error in the e-mail system caused the message to bounce between two servers or to be forwarded between two recipients. Contact your administrator. <ourservername.ourdomainname.com #5.3.5> It doesn't happen on all our e-mails, so it makes it really hard to troubleshoot. We only have one Exchange Server (Ex2003 SP2 Std Ed). This issue only seems to occur when we emailing a distribution group or a large number of single email addresses. Any ideas or thoughts would be most appreciated, thanks.

Hi, The NDR is typically an indication of mail-looping situation. This means that the server is configured to loop mail back to itself(go to SMTP Virtual server proprty--Delivery--Advance delivery--smarthost). If you have multiple SMTP virtual servers configured on your Exchange server, ensure that they are serving unique incoming ports. Also, to avoid looping between local SMTP virtual servers, ensure that the outgoing SMTP port configuration is valid. If you have SMTP connector then please check the configuration there as well to mitigate any loop situation. Regards, Pushkal MishrA

Hi, Please check whether Recipient A forwards to Recipient B who is set to forward to Recipient A or not. Please check the properties of routing connectors whether select option "Any local server can send email over this connector" Please check the properties of SMTP Virtual Server changed from "All Unassigned" to current IP address. http://support.microsoft.com/kb/326304 Thanks Your expertise never fails to impress!

can u check my settings through online ----

Sorry. You need check the setting in your exchange server. Please follow the below steps: 1.How to check whether Recipient A forwards to Recipient B who is set to forward to Recipient A or not Open Active Directory Users and Computers>find the problem users in OU>Right click the user's Properties>Exchange General>Delivery Options>Forwarding address>click None. 2.How to check the properties of routing connectors whether select option "Any local server can send email over this connector" Exchange System Manager>Right click the Properties of your exchange Fist Organzation>check both Display routing groups and Display administrative groups Exchange System Manager>Administrative Groups>Routing Groups>Connectors>Routing Group Connector> 3.How to check the properties of SMTP Virtual Server changed from "All Unassigned" to current IP address. Exchange System Manager>Administrative Groups>Servers>Protocols>SMTP>Right click the Properties of Default SMTP Virtual Server>Select IP addressYour expertise never fails to impress!