Releasing messages from quarantine

[Steve Freegard]

Jason Ede wrote:
>> Sure - in MailWatch conf.php set QUARANTINE_USE_SENDMAIL to 'true' and
>> it will send the original message without modification.
>>
> 
> I've found that isn't always reliable (on mailwatch 1.0.4) if there are attachments on the email. Mailwatch says that the email has been released but nothing ever seems to reach the mail queue... I think its some form of memory issue to do with PHP? If can get it working reliably would be fantastic :-D
> 

Actually the problem isn't with MailWatch - but the way MailScanner 
handles blocked attachment or file types.

When MailScanner sends notices it uses the original Message-ID header 
and replaces the body with the notice.

Certain mail servers (Exchange, Zimbra etc.) have duplicate message 
prevention built-in and they use the Message-ID header to determine 
duplicates, so if you send multiple messages with the same Message-ID - 
the first message will be delivered and the rest will go to /dev/null or 
NUL if you're a Windoze user ;-)

For users of systems that do duplicate message checking you have to do 
something like the following:

cat /path/to/message | grep -Ev '^Message-ID:' | sendmail -toi

And your MTA should see the missing Message ID and create one for you.

Kind regards,
Steve.