Validating Email addresses

Julian Field MailScanner at
Wed May 6 09:57:10 IST 2009

On 05/05/2009 18:55, Paul Lemmons wrote:
> We are getting a great deal of Spam bypassing both Postini and Mail 
> Scanner due to a discrepancy between how these two products define an 
> email address and the way Exchange does. The two scanning products 
> recognize emails with a pipe character "|" at the beginning of the 
> address as both valid and part of the email address. I believe this is 
> in line with the email standards. Exchange, othe the other hand simply 
> ignores the character. So a message sent to me at and 
> |me at are seen as two different addresses by the scanning 
> systems and as a single address by Exchange.
Set "Reject Messages" to point to a ruleset, and have a ruleset that 
looks roughly like this:
FromOrTo: /^\|/ yes
FromOrTo: default no
and MailScanner will reject messages coming from or going to an address 
starting with a pipe character.
Simple as that.
Remember to "service MailScanner reload" after changing the ruleset and 
MailScanner.conf file.


Julian Field MEng CITP CEng
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