New Hotmail deliverability solutions

By Jim Kinkade

Successfully delivering messages to Windows Live Hotmail email accounts recently became more challenging for legitimate mass email marketers. Included in this free email service are new message barriers designed to stop spammers but can also cause problems for subscription-based email messages as well. Some of these barriers include warnings in the user interface about possible phishing or spoofed email headers.

Most of this new technology in place is self explanatory, and is easily tested by monitoring a Windows Live Hotmail email account. Determining whether or not your email message is eligible for a Hotmail junk folder can be done by testing and adjusting message headers, subject lines and content of email messages.

Another new Hotmail practice is IP throttling, which restricts the number of inbound emails Hotmail will accept, per sender IP address until it reaches a consistent number of emails. Once reaching that number, then "sending permanence" is established and the throttling is supposedly lifted. According to Microsoft, consistency of IP address is imperative to reduce spam activity:

Sending "permanence" (Consistency) - Sending from the same IP address with consistent volumes and frequencies month over month is ideal. Spammers tend to "pop up" on an IP and disappear. Infrequent senders who send large volumes once a month or quarterly can be an indicator of a spammer or a compromised server."

What this means to new legitimate mass email marketers is that there will be an elimination period of sorts when sending to Windows Live Hotmail accounts. Until the magic threshold is reached, a new sender, using an unfamiliar IP, will not have much success sending to Hotmail accounts. Since Microsoft did not publish any of the thresholds, the marketer will have to guess how many Windows Live Hotmail mail addresses to include in a campaign.

Delivery strategies
Some strategies to help keep up Hotmail deliverability until the IP is recognized is to break out the affected addresses from the main campaign, and send the list in smaller chunks, until deliverability improves. Another option is to determine which of these affected accounts have a history of being responsive. Recipients with no opens or clicks recorded should be filtered out to ensure that only the most active Windows Live Hotmail accounts are included in a campaign. It is imperative that dormant Windows Live Hotmail accounts that show no activity for several months are culled, because after so much inactivity, those addresses are converted over to spam traps, and any legitimate marketing still sending to them will be caught.

The Smart Network Data Services program, or SNDS, provides general information on Windows Live Hotmail delivery issues for a specified mail server. Simply add the mail server's IP address to track and view where Hotmail is showing delivery problems. While the information is rather general, it is a valuable tool to help identify problems so they can be addressed.

Some examples of what Windows Live Hotmail sends on the SNDS program include spam filter results which are broken down into three categories, Green, Yellow, and Red, based on an aggregate score from a number of spam filter technologies in place. Unfortunately, the report does not explain what triggers a yellow or red score. A more valuable measurement is the spam complaint rate, which is the number of complaints divided by the number of emails in a 24-hour period. Windows' recommended target is under 0.3%. Once logged in, the SNDS provides a good breakdown of each feature it has tracked and what the results mean.

Windows Live Hotmail also introduced a new Junk Email Reporting program, where bulk email senders are invited to apply to help alleviate spam. After supplying a bit of information for the program, more data is shared after your information is verified.

If nothing else, signing up for this program can help you keep track of what's going on with Windows Live Hotmail -- the second largest email ISP provider on the Internet. Who knows, maybe it will eventually help get rid of spam too.

For more information
Windows Live Hotmail postmaster website

"Improving E-mail Deliverability into Windows Live Hotmail," document detailing all the new Hotmail features

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