SPF records: not really all that important

I’ve been working through some Hotmail issues with a client over the last few months. One of the things that has become clear to me is how little Hotmail actually does with SPF records. In fact, Hotmail completely ignored my client’s SPF record and continued to deliver email into the inbox.
This isn’t just a sender that had a “well, we think most of our email will come from these IPs but aren’t telling you to throw away email that doesn’t” record. In fact, this client specifically said “if email doesn’t come from this /28 range of email addresses, then it is unauthorized and should be thrown away.” The email was being sent from an IP outside of the range listed in the SPF record.
As part of the process involved in fixing the delivery problems, I had the client update their SPF record and then I enrolled their domain in the SenderID program at Hotmail. This didn’t have any effect, though. Hotmail is still not checking SPF for this client. When I asked Hotmail what was going on they said, “We do not do lookups on every sender’s mail.”
So, there you have it folks. The last bastion of SPF/SenderID has abandoned the technology. Even a totally invalid SPF record doesn’t matter, mail can still reach the inbox at Hotmail.

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ESPs, Non-portable Reputation and Vendor Lock-in

I’ve seen some mentions recently of ESPs suggesting that if you use your own domain in the From: of mail you send through an ESP then that ESP can’t “do email authentication” properly unless they require you to edit your domains DNS settings. That’s not really so, but there is a kernel of truth in there.
The real situation is, unsurprisingly, a bit more complicated.
What authentication features should you look for in an ESP?

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Breaking through the script

In handling day to day issues I use the ISP designated channels. This means I frequently get dragged into long conversations with people, probably outsourced to the far east, who can do nothing beyond send me a boilerplate.
This can be a frustrating experience when the issue you’re trying to deal with is not handled by the script. Generally, by the time someone has come to me for help, they are “off script” and I do need to actually talk to a human to get resolution.
With Hotmail, I’ve found that persistent repeating of very simple phrases will eventually get the issue kicked up to someone who can respond with something beyond another boilerplate. This can take days, but it is possible.
I’ve recently run into a Yahoo issue where I am trying to punch through the script, but have so far been unable to.
One of the services Word to the Wise offers is whitelisting. I collect info from customers, verify that what they’re doing will get them whitelisted at the ISPs that offer it, and then submit the information to the ISPs. Yahoo has recently moved to an online submission form for their whitelisting process, which is great for me. No more creating a giant document and then cutting and pasting the document into an email and then mailing it off.
The problem is, there seems to be a minor problem with the Yahoo Whitelisting submission form. When submitting an online application to Yahoo, they respond with a message that says “this application is not complete.”
I’ve been attempting to break through the script in order to find out what about the application is not complete. The webform has data checking, and you cannot submit a form while leaving any of the questions blank. Asking “what is wrong” when the application is kicked back has resulted in me having multiple copies of the whitelisting submission form.
It’s gotten so frustrating that I’ve escalated to personal contacts, but they can’t explain what’s not complete about the application as submitted online, either.
Has anyone had any success breaking through the Yahoo script? Has anyone managed to get IP addresses whitelisted through Yahoo using the online form?

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How to disable a domain

Sometimes you might want to make it clear that a domain isn’t valid for email.
Perhaps it’s a domain or subdomain that’s just used for infrastructure, perhaps it’s a brand-specific domain you’re only using for a website. Or perhaps you’re a target for phishing and you’ve acquired some lookalike domains, either pre-emptively or after enforcement action against a phisher, and you want to make clear that the domain isn’t legitimate for email.
There are several things to check before disabling email.
1. Are you receiving email at the domain? Is anyone else?
Check the MX records for the domain, using “host -t mx example.com” from a unix commandline, or using an online DNS tool such as xnnd.com.
If they’re pointing at a mailserver you control, check to see where that mail goes. Has anything been sent there recently?
If they’re pointing at a mailserver that isn’t yours, try and find out why.
If there are no MX records, but there is an A record for the domain then mail will be delivered there instead. Check whether that machine receives email for the domain and, if so, what it does with it.
Try sending mail to postmaster@ the domain, for instance postmaster@example.com. If you don’t get a bounce within a few minutes then that mail may be being delivered somewhere.
2. Are you sending email from the domain? Is anyone else?
You’re more likely to know whether you’re sending mail using the domain, but there’s a special case that many people forget. If there’s a server that has as it’s hostname the domain you’re trying to shut down then any system software running no that server – monitoring software, security alerts, output from cron and so on – is probably using that hostname to send mail. If so, fix that before you go any further.
3. Will you need mail sent to that domain for retrieving passwords?
If there are any services that might have been set up using an email address at the domain then you might need a working email address there to retrieve lost passwords. Having to set email back up for the domain in the future to recover a password is time consuming and annoying.
The domain registration for the domain itself is a common case, but if there’s any dns or web hosting being used for the domain, check the contact information being used there.
4. How will people contact you about the domain?
Even if you’re not using the domain for email it’s quite possible that someone may need to contact you about the domain, and odds are good they’ll want to use email. Make sure that the domain registration includes valid contact information that identifies you as the owner and allows people to contact you easily.
If you’re hosting web content using the domain, make sure there’s some way to contact you listed there. If you’re not, consider putting a minimal webpage there explaining the ownership, with a link to your main corporate website.
5. Disabling email
The easiest way to disable email for a domain is to add three DNS records for the domain. In bind format, they look like:

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