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External email not received with NDR '550 5.4.317 Message expired, cannot connect to remote server(C
Hi all, we are getting some problem from one of the external domain not getting through. there is a NDR to the sender '550 5.4.317 Message expired, cannot connect to remote server(CertificateExp...
The issue you're facing with external emails not being received is accompanied by a Non-Delivery Report (NDR) indicating '550 5.4.317 Message expiredhttps://pikashowhdapp.com/ cannot connect to remote server(CertificateExpired).' External tests using checktls confirm a connection conversion to SSL, highlighting a potential certificate expiration problem.