Patrik Lundin, patriklundin.info

Download FilterRecipients Here

This is a VBScript that checks the recipients of incoming emails to the default Windows 2003 SMTP/POP3 service.

The purpose is to avoid NDR's (Non Delivery Reports) from being sent out when spam is directed to a non existing mail account and thereby avoid NDR spam and NDR flooding attacks of third party servers.

It should be noted that strictly this breaks the rfc that specifys that a non delivery report must be sent out if an email is not delivered, but these days NDR attacks and spam have become a large problem and any usefulness is clearly overshadowed by these problems.

The script registers into the SMTP service, it will only work if you use the POP3 service on the same machine with mailboxes defined, if the SMTP service is used to forward emails to another server it will not be able to check the mailboxes.

For installation instructions please read the README.TXT in the download.

Obviously this is strictly use at your own risk, I do not take any responsibility for any emails that might get lost or any other damage that may occur.