TPG Email Active Sync Certificate not valid

[crusader_wabbit]

receiving a popup warning accessing e-mail via outlook 365 on Windows 10
"The server you are connecting to is using a security certificate that is not valid, the target principal name is incorrect"
issued to:  mail.tpg.com.au
issued by: Entrust Certification Authority - L1K

Valid from: 30/08/2023 to 30/08/2024

Can you please fix/repair certificate

[BasilDV · Accepted solution]

Hi @crusader_wabbit 

We may need to check the outgoing and incoming mail server along with the ports that you are using.

Please refer to the correct settings here: https://support.tpg.com.au/email-settings

Let us know how it goes.

[crusader_wabbit]

My accounts are ....@wn.com.au   and   ....@westnet.com.au   
I have been using the same settings for some time now without change so I think this is something on the Westnet/iiNet/TPG/internode side.
I do not actually reference a TPG domain name server at all, i am using iiNet domain name servers, yet I get a tpg certificate error.     (maybe all aliases of the same)

Incoming:    imap.iinet.net.au
       Port:   143    STARTTLS
Outgoing:   smtp.iinet.net.au
       Port:    587    STARTTLS

tracert mail.iinet.net.au

Tracing route to sep-kakadu03.au-east.atmailcloud.com [52.62.236.135]

tracert smtp.iinet.net.au

Tracing route to sep-kakadu03.au-east.atmailcloud.com [52.62.236.135]

tracert mail.tpg.com.au

Tracing route to sep-kakadu02.au-east.atmailcloud.com [54.206.19.13]

[crusader_wabbit]

I have changed from the iinet server to the TPG server
no longer receiving TPG certificate error
All seems OK thank you 

eg

Was:    mail.iinet.net.au      Now:   mail.tpg.com.au

From my perspective this error seems to point to a certificate issue on the server

tracert mail.iinet.net.au

Tracing route to sep-kakadu03.au-east.atmailcloud.com [54.153.230.49]

[BasilDV]

Glad that this has been resolved.

Thank you!