Technology Notebook

Internet Mail::MailSweeper

MailSweeper Issue
I want to ONLY receive mail from a single host and block mail from everybody else. (We are using a spam filtering service provider and I want to force all mail to go through them.) The tricky thing with MailSweeper (4.3.patched) is the banned host feature doesn't work when you try to restrict everyone then make an exception for the one that is allowed to send mail.
Fix (partly)
To work around this I removed all the relay target domains (to which relaying is allowed from any host) and setup the IP address of the desired server into the list of relay hosts. This explicitly defines what servers are allowed to relay off this server.
Additional issue
But this only worked for all my "secondary" domains. The primary domain still allowed inbound relaying to that domain from any host. Under the "SMTP Relay" policy folder the "domain object" specifies our "primary" or "default" domain. It doesn't seem to be necessary because I have used forced routes to get the mail delivered. I renamed this domain to NORELAY(domain).com and it worked. It accepted relays to the primary domain from the desired host(s) but when it generated Non-Delivery Receipts (NDR's) it showed up as from "postmaster@NORELAY(domain).com"
Getting rid of the domain object
There were no useful properties of this object and there is no way through the policy editor interface to delete it.

- close MMC
- edit MAILSWP.CFG file
- find and delete the following section:
[MailServer\(domain).com]
- find and delete the following line from the [MailServer] section:
k:(domain).com=Domain

But there are still some NDR's that seem to use that address. The silly thing is there is a configuration setting where I tell it the address for the administrator = postmaster@(domain).com

ClearSwift MailSweeper is a Windows internet mail relay server product that will apply content policies/etc.
See more at: http://www.mailsweeper.com/products/msw/smtp/default.asp