[webmin-l] Postfix Settings unexpectedly break postfix...

[Richard C. <rch...@aa...>]

I want postfix to be able to send outgoing email from my local network - 
but also to be able to send outgoing email from SASL Authenticated 
clients outside this network. Obviously I don't want "non-authenticated" 
clients outside my network to be able to send.

My settings in the postfix/smtp authentication and Encryption page were 
as follows - but Authenticated clients couldn't seem to send from 
outside. Unfortunately - I don't have a record of the error message they 
received.
My Logwatch file shows that at least some clients are being SASL 
authenticated - so I think SASL is basically working.

Enable SASL Authentication's = yes.
Reject Anonymous Logins is checked.
Allow connections from same login is checked.
Allow authenticated clients is checked.
Reject email to other domains was checked.

Everything else = unchecked.

I think the other settings are irrelevant.
I assumed that the last of these settings (reject email to other 
domains) might have been the problem - so I unchecked it and restarted 
postfix.

It seems that that completely stopped postfix. While the process is 
running - it wont accept any connects from anyone - and all my normal 
incoming mail deliveries ceased.

I reversed the last setting several times - and it consistently breaks 
postfix whenever the "Reject email to other domains" is unchecked.

Any ideas why this might be so?
Any one else have a postfix configuration which allows remote 
authenticated relaying?

Thanks
Richard.