Delivery Delay

Question

Hi,

We updated Exchange server 2016 because the emails are taking a long time to deliver.

Could I know why it happened?

Anyone had similar delivery issue with Exchange server 2016?

220 xxxx-ES16.xxxxaust.local Microsoft ESMTP MAIL Service ready at Thu, 12 May 2022 11:33:37 +1000",
250 xxxx-ES16.xxxxaust.local Hello [xxx.52.199.19] SIZE 37748736 PIPELINING DSN ENHANCEDSTATUSCODES STARTTLS X-ANONYMOUSTLS AUTH NTLM X-EXPS GSSAPI NTLM 8BITMIME BINARYMIME CHUNKING XRDST,
EHLO <server>.<domain>.com.au,
STARTTLS,
220 2.0.0 SMTP server ready,
CN=xxxx-ES16 CN=xxxx-ES16 3C87xxxD10249D9B48E14C214A841920 A936E77FCD0E7771BC9B0EDDB4F706556C4708FC 2019-12-11T14:55:05.000Z 2024-12-11T14:55:05.000Z xxxx-ES16;xxxx-ES16.xxxxaust.local,Sending certificate Subject Issuer name Serial number Thumbprint Not before Not after Subject alternate names
"TLS protocol SP_PROT_TLS1_2_SERVER negotiation succeeded using bulk encryption algorithm CALG_AES_128 with strength 128 bits, MAC hash algorithm CALG_SHA_256 with strength 0 bits and key exchange algorithm CALG_ECDH_EPHEM with strength 256 bits"
<server>.<domain>.com.au,
Client certificate chain validation status: 'EmptyCertificate'
TlsDomainCapabilities='None'; Status='NoRemoteCertificate'
xxxx-ES16.xxxxaust.local Hello [xxx.52.199.19] SIZE 37748736 PIPELINING DSN ENHANCEDSTATUSCODES AUTH NTLM LOGIN X-EXPS GSSAPI NTLM 8BITMIME BINARYMIME CHUNKING XRDST,
MAIL FROM:<scanner@xxxxxxxxxxxxx .com.au> SIZE=1992773,
08DA32F4216E6D00;2022-05-12T01:33:38.333Z;1,receiving message
RCPT TO:<brett@xxxxxxxxxxxxx .com.au>,
BDAT 2579,
Proxy destination(s) obtained from OnProxyInboundMessage event. Correlation Id:92db13cf-9bce-4e37-9be2-98b59347e2b4
50 2.1.0 Sender OK,
250 2.1.5 Recipient OK,
250 2.6.0 CHUNK received OK, 2579 octets",
BDAT 1989171 LAST,
250 2.6.0 <627CEE33.05E.00206B46C996.scanner@xxxxxxxxxxxxx .com.au> [InternalId=90933047590962, Hostname=xxxx-ES16.xxxxaust.local] 1993176 bytes in 0.355, 5476.220 KB/sec Queued mail for delivery",
Local

xxxx-ES16.xxxxaust.local Microsoft ESMTP MAIL Service ready at Thu, 12 May 2022 11:33:39 +1000",
EHLO <server>.<domain>.com.au,
250 xxxx-ES16.xxxxaust.local Hello [xxx.52.199.19] SIZE 37748736 PIPELINING DSN ENHANCEDSTATUSCODES STARTTLS X-ANONYMOUSTLS AUTH NTLM X-EXPS GSSAPI NTLM 8BITMIME BINARYMIME CHUNKING XRDST,
STARTTLS,
220 2.0.0 SMTP server ready,
2CN=xxxx-ES16 CN=xxxx-ES16 3C87xxxD10249D9B48E14C214A841920 A936E77FCD0E7771BC9B0EDDB4F706556C4708FC 2019-12-11T14:55:05.000Z 2024-12-11T14:55:05.000Z xxxx-ES16;xxxx-ES16.xxxxaust.local,Sending certificate Subject Issuer name Serial number Thumbprint Not before Not after Subject alternate names
TLS protocol SP_PROT_TLS1_2_SERVER negotiation succeeded using bulk encryption algorithm CALG_AES_128 with strength 128 bits, MAC hash algorithm CALG_SHA_256 with strength 0 bits and key exchange algorithm CALG_ECDH_EPHEM with strength 256 bits"
EHLO <server>.<domain>.com.au,
Client certificate chain validation status: 'EmptyCertificate'
TlsDomainCapabilities='None'; Status='NoRemoteCertificate'
250 xxxx-ES16.xxxxaust.local Hello [xxx.52.199.19] SIZE 37748736 PIPELINING DSN ENHANCEDSTATUSCODES AUTH NTLM LOGIN X-EXPS GSSAPI NTLM 8BITMIME BINARYMIME CHUNKING XRDST,
MAIL FROM:<scanner@xxxxxxxxxxxxx .com.au> SIZE=361315,
08DA32F4216E6D02;2022-05-12T01:33:39.985Z;1,receiving message
RCPT TO:<shane@xxxxxxxxxxxxx .com.au>,
BDAT 2579,