Bigpond email SSL certificate expired

[Lumberman692]

Dear All,

I cannot send email to a few clients with the following SSL certificate expired message

What do I do... The call centre are really bad, waiting for several times on the phone for min 1 hour at a time.....

This Message was undeliverable due to the following reason:

Each of the following recipients was rejected by a remote mail server.

The reasons given by the server are included to help you determine why

each recipient was rejected.

    Recipient: <Paul.Laing@redstagtimber.co.nz>

    Reason:    TLS client certificate is expired or not yet valid

    Recipient: <Steve.Goldsmith@redstagtimber.co.nz>

    Reason:    TLS client certificate is expired or not yet valid

The original message has been removed from the bounce message.

Reporting-MTA: dns; nsstlfep03p.bpe.nexus.telstra.com.au

Arrival-Date: Fri, 28 Feb 2020 10:01:55 +1100

Received-From-MTA: dns; smtp.telstra.com (10.10.24.4)

Final-Recipient: RFC822; <Paul.Laing@redstagtimber.co.nz>

Action: failed

Status: 5.1.1

Remote-MTA: dns; mx.redstag.co.nz (180.235.104.209)

Diagnostic-Code: smtp; 550 TLS client certificate is expired or not yet valid

Final-Recipient: RFC822; <Steve.Goldsmith@redstagtimber.co.nz>

Action: failed

Status: 5.1.1

Remote-MTA: dns; mx.redstag.co.nz (180.235.104.209)

Diagnostic-Code: smtp; 550 TLS client certificate is expired or not yet valid