While waiting for that free time you could try testing the RCPT daemon I wrote some time ago. It's available in the download section:

http://community.pmail.com/files/folders/community_add-ons_for_mercury/entry10133.aspx

/Rolf

I've found that if you enable accept mail for invalid local addresses I get lower dictionary harvesting scans. but I find that Merc still create Failure delivery notification which I want to evade.

I've tried to add lines to transflt.mer

-------- 

R, "*<username from aliases_1>@<local domain>*", X, "Normal user mail detected"

...
R, "*<username from aliases_n>@<local domain>*", X, "Normal user mail detected"

R, "*@<local domain>*", D, "Spammer using Dictionary Harvester"

-------- 

Above method works mostly untill I forget to Add new alias to Filter :)

I've also tried to set "Limit maximum number of failed RCPT commands to" = 0 but that do not block msg from entering system.

 Is there something I've missed in settings or there is way to do fight it?

You could get rid of the Delivery Failure template, but then legit errors won't get reported to legit senders.

Your "Limit..."=0 will blacklist anyone who misspells an address, which is probably a bad idea.

Your transflt rule will drop anyone who misspells an address, which is probably a bad idea.

Also, the sending server will just retry anyway, as it has not been issued a Permanent Failure.

Resistance is futile! [:P]

I just reject invalid addresses at SMTP time. The SMTP reject goes to the sending server, so there is no backscatter as with DFN's to forged FROM addresses.

As for the spammers harvesting my addresses, they have them from other sources anyway, and it does them no good because of Spamcop, my transflt rules & Spamhalter which stop all but 1 in 1000 attempts.

Thx dilberts_left_nut,

I know it is futile but still I want to try. It is easy when you use http://en.wikipedia.org/wiki/Smarthost to receive and relay all your domain Emails Using MercC where your ISP has already done filtering of all incomming mails.

So what are your suggestions (Block Invalid local users) and can you help me set things up is Spamcop available for mercury?

I wonder if Daemon could be made  to add this kind of feature?

[quote user="Peke"]

Thx dilberts_left_nut,

I know it is futile but still I want to try. It is easy when you use http://en.wikipedia.org/wiki/Smarthost to receive and relay all your domain Emails Using MercC where your ISP has already done filtering of all incomming mails.

[/quote]MercC is the relaying client for outbound SMTP. If your ISP is filtering your ALL incoming mail then you are using MercD to POP it from a 'domain box'? Why have MercS listening on your public interface?

 [quote]

So what are your suggestions (Block Invalid local users) and can you help me set things up [/quote]depends on your setup and what you are really wanting to do[quote]is Spamcop available for mercury?[/quote]Yes, there are controls for DNSBL's in the MercS config menu[quote]

I wonder if Daemon could be made  to add this kind of feature?

[quote user="dilberts_left_nut"]MercC is the relaying client for outbound SMTP. If your ISP is filtering your ALL incoming mail then you are using MercD to POP it from a 'domain box'? Why have MercS listening on your public interface?[/quote]

I do not use MercC but MercE.

I'm lucky as my ISP do not filter incoming mail at all. Only ports that he filters are 80, 81, 82, 8080 and 8081 :)

I only use MercD to collect all mails from my other POP3 accounts and delivering to local account.

 I see that Daemon SDK is Available in Delphi. I think I'll give it a try as soon as I catch some free time and try to make some RCPT Filtering Daemon.