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Useful Blacklists?

By CGriffith318 ·
I'm looking for some feedback on some useful blacklists. I would like to have one that updates frequently. Please list where to find it and your experience with it.


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Problem with RBL's

by Oz_Media In reply to Useful Blacklists?

To select a blacklist check on it's own for filtering SPAM is asking for a MAJOR headache.

Almost all popular free domains are blocked by ALL RBL's, Yahoo, Excite, Shaw, MSN etc. NOBODY's mail will get through.

RBL's are not reliable as a single source, if coupled with a heuristic scan it will be easier but then you will need a high end antispam product such as Beginfinite's GWAVA or Guardian from GWTools. BOth o these products, GWAVA especially were originally designed for GroupWise and Novell, as they got VERY popular VERY fast they are now fully MS compatible. Gwava is pretty cheap at just under $1000.00 US and does what MOST Spam protectors don't. It offers full virus scanning BEFORE the MTA (including ZIP and other compressed attachments), it provides a heuristic list with customizable word weighting as well as an RBL check. For eg. If I set a threshold of 4.0 and the first scan says the word FREE scores a weight of 2.5 then anyother words or tests that o over the preset threshold makes it SPAm and it is archived for later recovery by the admin if needed. What I do is set my RBL tests to add a weight of 3.0 IF it is on an RBL list, then ANY keywords I have entered will automatically put it over the threashold I have set and it is spam, but it is not considered SPAM based solely on the RBL results, they just aren;t worthwhile. MANY RBL lists are just home or high school projects where they nail everyone for the most retarded reasons. Eg. I use a GroupWise email server, groupwise will ACCEPT mail that is forwarding but will not actually forward it. For this reason, I my domain blacklisted until I proved to the KIDDIES that ran the site they were wrong in assuming that if it is accepted it will be relayed.

I do have a list of about 12 RBL engines that I use but as I say, only as a pre-scan not a final decision. When I first started using GWAVA I had it set to check RBL's and archive the email from the lists, each day I would recover over 1100 False Positives every day or two(real and wanted email blocked by the RBL lists). I had customers, sales reps, owners and managers going NUTS!! I changed RBL testing to be a preliminary check and now perhaps see 1-3 false positives at most each WEEK.

So in a nutshell, if people are relying on you to get their email to them DO NOT USE AN RBL LIST AS A FINAL DECISION!! They are poorly managed junk and it can take weeks for someone to be removed from one.

SPAM protection for a business requires on of two things.

A REALLY tight script (pythonm works well) to perform a heuristic email scan for keywords. or
spend the cash to get the right products, Spam Assassin etc are just toys for home users but not effective in a working environment.

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