For the past couple of weeks, I've been trying to get my domains unblocked from Hotmail/Live. I set up a new domain for Barebones CMS (barebonescms.com) and put forums on the site and forgot to add a SPF record for the domain. A couple weeks ago, Hotmail/Live servers decided that e-mail from barebonescms.com was invalid and therefore refused delivery. Due to the holidays being crazy, I was unable to get around to dealing with the problem.
Then I discovered that Hotmail/Live was actually blocking ALL e-mail from my e-mail server regardless of domain. This sent me on a search to see how I could get unblocked. Of course, the first step was to fix my DNS records to add a SPF record. SPF-aware mail servers should really be assuming a default of:
v=spf1 mx -all
v=spf1 a mx -all
That way, most of us don't have to fiddle with silly things like this.
The next two steps to getting off the Hotmail/Live block list is to go here:
And request to join both the "SenderID" and "Junk Mail Reporting Partner" programs. Those are the minimum required to get off their block list. Of course, because of Internet delays revolving around e-mail and DNS, it can take 24+ hours before any changes are to be made to their servers and then another 48+ hours to take effect.
During this process, I ran into a couple nifty little tools that everyone who runs an e-mail server should be using:
Sender Score is a pretty accurate measure of how much e-mail volume a specific IP address is churning out. The score is calculated based on anonymous ISP data. Hotmail/Live appears to use this information to determine the reputation of a specific IP address, which is likely used in their spam filter to determine whether to accept the message, drop it in the spam folder, or simply reject the message altogether. The graph they display is really nice for determining trends for a specific IP but is otherwise meaningless.
The other nifty tool I ran across is Microsoft Postmaster Smart Network Data Services. This tool is a little more difficult to set up but you can see issues regarding the specific IP address associated with a mail server. For example, if someone reports an e-mail as spam or Hotmail/Live detects a virus coming into their servers from a specific IP, that information is made visible using that tool.
All of this takes time to complete. By the end of this week, though, my own situation should be cleared up. Hopefully this helps someone else. The moral of this story is: Don't forget to set up SPF records on new domain names.