It appears I partly fixed this issue during last nights discussions without realising it.
Checking the Opera log this afternoon showed the error message had changed to: 503 5.5.1 Error: authentication not enabled Last night I replaced the /etc/hosts file with 127.0.0.1 localhost 192.168.0.1 veyron.local veyron so that fixed the initial problem but introduced another. So I retraced everything I had changed or turned on/off. Turns out I had forgotten to turn off SMTP authentication; my ISP does not require it. Normal transmission has been resumed. I checked Steve's link to FQDN and could find no trace of any entry in any .ini file. Turns out on more recent versions, if there is no entry Opera automatically detects it. I am not sure however how/why the hosts file got mangled. Thanks for your help guys. Cheers, Chris