Event ID - 4007

Event Id4007
Sourcesmtpsvc
DescriptionMessage delivery to the host<IP address>failed while delivering to the remote domain gmx.de for the following reason: An SMTP protocol error occurred. The SMTP verb which caused the error is MAIL. The response from the remote server is<name>Cannot resolve your domain.
Event InformationAccording to News Group:
Setup POP3 & SMTP services on the server. After these services are started, slowly but surely "inetinfo.exe" grabs as much memory as it can. This is strange as my server serves an extremely small email user-base as well as a couple low-traffic sites. Look into the Event Viewer and try to noticed server is getting hit pretty hard with requests to send email (not inside clients); both in-bound and out-bound servers are password protected, so unless the user successfully authenticates the request is rejected. Make limited the number of connections to in mailserver in an attempt to keep memory usage to a minimum. This seemed to slow the mad rush to usurp memory, but eventually "inetinfo.exe" still walks away with a hefty chunk.
Reference LinksWindows Small Business Server 2003

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