Get online support
Reported it to TPG Thursday, after long time on phone. Saturday told I have to send issue to postmaster@tpg.com.au. Still waiting Monday for any response.
Also, have not stopped RECEIVING emails on my accounts (5 DIFFERENT ACCOUNTS). Just can't send anything.
Get immediate bounce of:
TPG SERVER
The following recipient(s) cannot be reached:
'***@***.com' on 12/06/2020 5:48 PM
Server error: '550 5.7.1 <'***@***.com>... Relaying denied. IP name possibly forged [220.253.127.243]'
OTHER EMAIL SERVER:
The connection to the server was interrupted. ... The Server responded: 550 https://www.spamhaus.org/query/ip/220.253.127.243
PBL say need to turn on "SMTP Authentication" in your email program settings.
THEN
220.253.0.0/16 is listed on the Policy Block List (PBL)
Have a look at this post. Scroll down to the part with the red print.
You need to turn on SMTP authentication.