Yahoo and their mail filters..

Brian Keefer chort at
Fri Feb 27 04:17:37 UTC 2009

On Feb 26, 2009, at 5:08 PM, J.D. Falk wrote:
>> Blocking an entire site just because one John Doe user clicked a  
>> button
>> they don't even understand just does not make sense.
> You're right -- but Yahoo! has a sufficiently large userbase that  
> they can count multiple complaints before blocking anything.  Same  
> story with AOL, and Hotmail, and Cloudmark, and many others who've  
> used this technique for years.

This does not appear to be the case from external observation.  It may  
be in some cases that multiple reports are necessary, but it certainly  
seems there are hair-triggers in others.  For instance, see the  
message from Eric Esslinger.

As for not black-holing anything, I haven't personally verified with  
Yahoo!, but others have reported that they do.  It's pretty common  
from what I've seen to simply make very high-scored messages disappear  
and only send the mid-range stuff to the spam folder.  Hotmail, as  
mentioned, does this.  One of the very large hosted filtering services  
does as well.  I'm not saying it's bad (it makes sense if you can  
trust your scoring algorithm), but it does happen.  Just because you  
get _some_ stuff in your spam folder doesn't mean that's all the spam  
that was blocked.


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