[Mimedefang] rejecting invalid users

[Kevin A. McGrail]

> currently all invalid recipients emails go to mail gateway and then
exchange
> server bounce it  . i want to reject invalid recipients at mail gateway
>
> can i do this with mimedefang or sendmail ??

SD:

With Exchange 5.0, you have to do lots to configure LDAP on an alternate
port, etc.

With Exchange 2000, use LDAP to export the list.  Here are some notes from
Patrick Morris about how he used Sendmail to do it.
http://www.peregrinehw.com/downloads/sendmail/current-8.12.X/untarred/contrib/ldap_notes.
However, I preferred Brian Landers' method and I enhanced it for my needs
and published a walk-through at
http://www.peregrinehw.com/downloads/ldap/INSTALLj

With Exchange 2003, implement a recipient filter like below and use MD's
filter_recipient feature with md_check_against_smtp_server.

Based on MS Knowledge Base:

First, create a recipient filter -

To create a recipient filter, follow these steps:
1.      Start Exchange System Manager.
2.      Expand Global Settings, right-click Message Delivery, and then click
Properties.
3.      Click the Recipient Filtering tab.
4.      [Intentionally Deleted by KAM]
5.      To filter messages that are directed to e-mail addresses that do not
exist in your organization, click to select the Filter recipients who are
not in the directory check box.


Next, apply the filters to the SMTP virtual server -

Apply the connection filter or the recipient filter or both to the
appropriate SMTP virtual servers
You must enable the connection filters and the recipient filters on each
SMTP virtual server where you want these settings to be applied. To apply a
filter to a SMTP virtual server, follow these steps:
1.      Start Exchange System Manager.
2.      Expand Servers, expand Server Name, expand Protocols, and then
expand SMTP.
3.      Right-click the SMTP virtual server where you want to apply the
filter, and then click Properties.
4.      On the General tab, click Advanced.
5.      Click the IP address that you want to apply the filter to, and then
click Edit.
6.      In the Identification dialog box, click to select either the Apply
Connection Filter check box or the Apply Recipient Filter check box.
7.      Click OK, click OK, click Apply, and then click OK.
8.      Restart the SMTP virtual server where you applied the filter.
9.      Repeat steps 2 through 8 for each virtual server where you want to
apply the filter.