Whoa, I have Imail set up so that it deletes any spam that is listed on 3 or more blacklists, which do not generally overlap unless there is actual spamming activity going on. I had these messages tagged within the headers for over a month before I decided to start sending them to the NUL folder, and had not received a SINGLE false positive from any e-mail that had been included on 3+ lists. For my more conservative hosting customers I have set the limit to 4, prior to deletion. I certainly would not trust any single RBL for the decision as to whether or not to delete.
As long as you are not using overly zealous blacklist services such as XBL or Five-Ten (who blacklist ANY e-mail coming from Yahoo.Com, for example), I believe, and know from extensive testing that such tests constitute a more than reasonable detection system. My only complaint is that it does not catch ENOUGH spam. It has never produced a single false positive though. Just choose your RBL's wisely and do a lot of testing first. Anyone who is using a provider that is on 3-4 blacklists is going to have all their mail blocked by AOL and many other ISPs as well. Blacklists are not the only method you should use to test spam, but it is the best first line of defense, I have found. You can't tell me or my subscribers that they do not work, nor that such a system traps a number even as high as .1% as false positives. Like I said, for over a month, using this system produced NONE. William Van Hefner System Administrator TheDigest.Com/TelCompare.Com > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of Matt Robertson > Sent: Thursday, September 04, 2003 9:39 AM > To: [EMAIL PROTECTED] > Subject: RE: [IMail Forum] Other Spam options > > > http://www.declude.com/junkmail/support/ip4r.htm > > As has been mentioned before what you use depends on your spam profile. > > > Since Imail doesn't have a weighting system, and kills any matches with > a single ding, I would use blacklists with *extreme* caution, given the > high percentages of false positives you can expect. > > Personally I don't use them at all inside of Imail and regard this > portion of its anti-spam as unsafe to use dor this reason. > > -------------------------------------------- > Matt Robertson [EMAIL PROTECTED] > MSB Designs, Inc. http://mysecretbase.com > -------------------------------------------- > > . > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Glenn Bullion > Sent: Thursday, September 04, 2003 7:36 AM > To: [EMAIL PROTECTED] > Subject: [IMail Forum] Other Spam options > > > More and more spam is coming through our server, yet I have made no > changes to our spam settings. It worked very nicely for a while, and > judging from the size of the spam box, it's still working. I guess the > spammers are just getting smarter. The only changes I can really think > of making is adding more blacklists. Can anyone recommend some decent > blacklists besides the ones already configured in Imail? > > > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html > List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ > Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ > > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
