553 sorry, that domain isn't in my list of allowed rcpthosts (#5.5.3 - chkuser)



Hi all,

I am running exchange 5.5 + sp4. Now very recently from today morning
I am having this message for all external emails sent from this server.

QUOTE

The recipient name is not recognized
The MTS-ID of the original message is: c=US;a=
;p=LTR;l=LTR2IBM-060515042052Z-74
MSEXCH:IMS:LTR:LTR2DOMAIN:LTR2IBM 3553 (000B09B6) 553
sorry, that domain isn't in my list of allowed rcpthosts (#5.5.3 -
chkuser)

UNQUOTE

I am able to receive emails. Anybody please help.

Regards
Sankara Raman

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