[ Date Index ] [ Thread Index ] [ <= Previous by date / thread ] [ Next by date / thread => ]
On Thu, Mar 28, 2013 at 10:10 AM, Simon Avery wrote: > There might be something buried in the headers to show it went through > a server belonging to a freemail provider, but I wouldn't like to > guarantee or monitor it to ensure no ham got hung up. Unless I misinterpret what you're saying, it's relatively easy to determine whether an email was sent from one of the (big) freemail providers. The reverse DNS of the connecting IP is usually the biggest give-away; most of these providers will also add a DKIM signature to the emails. But I doubt that helps a lot here. I did some back-of-the-envelope calculations and found that around 1% of email from legitimate Yahoo accounts (i.e. accounts not set up by spammers) was spam as a consequence of the account being compromised. Other webmail providers (I checked Hotmail and Gmail) performed better than that (especially Gmail). YMMV of course, but even if 10% of email from Yahoo were spam, blocking them would see you throw a lot of babies with the bathwater. Of course, your servers your rules and enabling moderation for Yahoo on a list server may not be a bad idea - depending on the amount of Yahoo subscribers and the time you can spend moderating emails. As to why Yahoo still hasn't solved it, we can only guess. They probably have bigger problems to deal with. Martijn. -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/listfaq