We have a issue with one of our suppliers from germany who up until May was able to send us email. Since then they are unable to send us email and they keep getting the following message:
#< #4.4.2 X-Postfix; lost connection with mail.ihs-aust.com.au[18.104.22.168] while sending MAIL FROM> #SMTP#
It coincided after we installed AVG Antispam on a SBS 2003 server running exchange 2003. i have since removed the
software but the problem still persists proving that it was not that as I did whitelist the email senders and domain.
After removing the software completely we still have the same problem.
I am not sure what to do with this and the management is getting frustrated.
Any assistance appreciated.