Microsoft breaks DKIM signature?

It's kind of rare, but not rare enough. Every now and then I hear of a client who is seeing intermittent DKIM failures at Microsoft Outlook.com/Hotmail properties. A Delivery Team Lead for one of the bigger ESPs posted about this on the Mailop list recently, looking for feedback and thoughts. The discussion that ensued seemed to come to a consensus that there are (rare) times when Microsoft may be modifying message content slightly, and thus causing the DKIM signature to break.

What You Need to Know About DMARC and Deliverability

Bronto's Chris Truitt explains how DMARC works, how it impacts deliverability and he outlines things to consider when configuring your DMARC record.

Spam Museum Welcomes 100,000th Visitor

From the not-just-email department: Local TV station KAAL-TV reports that the Hormel Spam Museum in Austin, Minnesota welcomed its 100,000th visitor last week. Her prize? 200 can of Spam. Yum.

Yuck: iCloud Calendar Spam

Are you one of the many millions of unlucky souls receiving spammy calendar invites? Apple is apparently aware of and working to address this type of thing, according to the iMore blog. But if you can't wait for that, the Verge has a few suggestions on what you can do about it.

Virgin Media is so rustic and artisan you get to hand-sort your own spam

Can't beat that headline. UK ISP Virgin Media is having a few problems with its spam filters, reports the Register. Previously hosting user mailboxes on Google-managed systems, the ISP was forced to bring it back in house after Google stopped selling the service to ISPs. Apparently, hilarity has ensued.

Good news for senders: Instead of blocking mail outright, suspected spam will now be routed to the spam folder. Sounds like ISP users will be able to identify spam and non-spam to the ISP, to help improve the filter over time.

A quick search suggests that @ntlworld.com and @blueyonder.co.uk are probably the relevant Virgin Media email domains affected by this issue. I'll update this post if I learn more.

MegaRBL DNSBL FUBAR

Over on the Word to the Wise blog, Laura Atkins explains what happened with that spate of short-term MegaRBL DNSBL listings you may have noticed last week.