exch2003sp2 on w2k3sp2, with backend + frontend servers deployment
now got strange, unpredictable ndr especially when sending to a particular email domain "example.org" in which we got Event 3030 NDR (status code 2.1.5 for recipient xxx@example.org) & Event 10009 DCOM (unable to communicate with smtp.example.org <--which is the smtp server of the recipients)
say in 15:51 got the ndr, in 15:52 the sane sender forward the rejected email to the same xxx@example.org recipient, it went thru without problem....
wondering how can i further narrow down the issues & fix it? many thx!
now got strange, unpredictable ndr especially when sending to a particular email domain "example.org" in which we got Event 3030 NDR (status code 2.1.5 for recipient xxx@example.org) & Event 10009 DCOM (unable to communicate with smtp.example.org <--which is the smtp server of the recipients)
say in 15:51 got the ndr, in 15:52 the sane sender forward the rejected email to the same xxx@example.org recipient, it went thru without problem....
wondering how can i further narrow down the issues & fix it? many thx!