mail issues questions

[Nadav Har'El]

On Tue, Mar 01, 2011, Geoff Shang wrote about "Re: mail issues questions":
> >Yahoo and Hotmail are very important. Why did you set up SPF and DKIM?
> 
> SPF and DKIM are technologies which should make it more likely that your 
> mail will be accepted, not less.

If you set them up *incorrectly*, it does make your mail less likely to be
accepted. E.g., if I say using SPF that mail from xyz.com should be coming
from mailer.xyz.com, and yet send such mail using somewhere.com's mail server
(e.g., because somewhere.com is my upstream internet provider and I want to
use their mail server), then my mail will be rejected.

> It turned out that another Roadrunner customer who had subscribed 
> willingly to one of our mailing lists had decided that they didn't want to 
> receive it anymore, and rather than unsubscribe normally, they were 
> marking messages which came from this list as spam.  Roadrunner's systems 
> then automatically flagged all mail from our server as spam, meaning that 
> no Roadrunner customer could receive any Email from our server at all.

This, and similar, anecdotes are examples of flawed spam filtering techniques.
The whole point of spam is that *a lot* of people get it. If just one person
complains, it most likely *isn't* spam.

-- 
Nadav Har'El                        |     Tuesday, Mar  1 2011, 25 Adar I 5771
nyh at math.technion.ac.il             |-----------------------------------------
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