Prevent user(s) from using outgoing smtp

[turnersloane]

For many years we have allowed clients to send email through our servers via their domains (ie, mail.exampleclient.com). About a year ago we began requiring new clients to use their ISP's outgoing mail servers (ie, mail.att.net) because of some increased cost in bandwidth. Even existing clients complied with our request (most are business clients who have at least fractional T-1's and don't mind using their ISP's bandwidth for outgoing mail).

Recently, one client - sneaky devils they are - discovered that after updating to a "business class" DSL connection, they can now send email via their domain (previously they were on a "residential" DSL connection and could not connect to our Port 25 because their IPS prevented outgoing connections to others' Port 25).

In this economy, we don't want to lose any clients - but we'd like to get this client to comply with our policies.

I've searched, googled, yahoo'ed, dogpiled and looked everywhere for a solution. Running an SMTP limiter isn't out of the question, but I don't think it will really help. The main problem is that this client likes to email large files to her clients - instead of simply uploading the files to her website and sending a link via email, she claims that her clients are women and don't want to click on a link as it it's too much trouble for her clients (seriously, I'm not making this up). I've even set up various mailing list software, but alas, to no avail.

Without losing the client, what options do I have? I'll gladly accept any hint....

Best to all,
sloane

 

[floyd]

As I understand it a person can only use your server to relay mail under 2 conditions.

1. They use authentication and port 587.
2. They check their mail prior to sending on port 25.

This is what I would try first:
1. Comment out the authentication section in exim.conf.
2. Stop running da-popb4smtp.

As usual other suggestions welcome.

 

[nobaloney]

Sloane, my guess is that since the client has explained why they want to use their server, and since they now know that they can on their business class connection, if you disallow their sending email, you probably will lose the client.

So how about just telling them how much you're going to charge them extra if they need to send that much data through your server?

Jeff