View Single Post
Old 05-24-2010, 09:46 AM  
Varius
Confirmed User
 
Industry Role:
Join Date: Jun 2004
Location: New York, NY
Posts: 6,890
GFY Educational Series: Improve Your E-Mail Inbox Deliverability Rate

In this installment of the "GFY Educational Series", I'd like to touch on a topic that is critical to many businesses, but often misunderstood. The information is out there, but it takes quite a bit of digging to put the pieces together. It's my hope that I can save some of you that work and improve your bottom line with a few simple changes in how you manage your mailing campaigns.

This article is meant for legit, compliant mailing and not those looking to simply engage in mass spamming. This article will touch on mostly technical aspects of mailing and not approach it from a marketing sense, as we have already had an excellent Series article regarding that aspect.

1) IP Addresses

The first thing you need to do, above and beyond all else, is understand your current IP address and its history. You may have ordered a new server at your current host, moved to a new host or been guaranteed to have a "fresh" IP. You should not just take anyone's word for this; verify those claims yourself. There are numerous free tools to investigate IP addresses, so I'll let you find your favorite, but here is a checklist of what you are looking for:

- IP found on Blacklist(s). If your IP is found on a Blacklist and was a new IP given to you by your host, demand they give you a different one. Most Blacklists don't answer remove requests promptly (or at all). If this is an IP address you have been using for awhile though, as you'll see later in this article, it may have benefits to trying to "clean" it as opposed to starting from scratch with a new IP.

- IP in "Neighbourhood" found on Blacklist(s). If there is an IP on your C Class that is allocated to another client of your host who has a bad reputation for their mailing practices, this may affect your delivery. As above, get yourself a new IP on a different Class or possibly even change hosts (as you don't want to be associated with a host who is lenient towards spammers).

Except in rare cases, you should also not rotate IPs when you send mail out. This may work short-term, but ultimately causes you more hassle than it's worth long-term as well as preventing you from being granted whitelist status at many ISPs. If your volume of mail requires multiple dedicated mailservers, so be it, but try and limit this as much as possible. If you have several load-balanced webservers, simply have them relay their mail through a single dedicated mailserver (or cluster if absolutely needed). For redundancy, you should always have a backup mailserver ready to take over the original's IP and MAC address to takeover operations.

I also recommend that for separate websites, you use separate IP addresses when possible. This is akin to "not putting all your eggs in one basket". If one IP or site gets blocked, your other sites are not immediately "guilty by association".

Once you have verified your mailserver's IP address is clean, you are not in a bad neighbourhood and you are not rotating dozens of IP addresses, you have completed Step1

I recommend you setup regular monitoring of your IP address' reputation (either manual or automated), so you can be alerted if your situation ever changes and not let days go by wondering why your conversions/sales have dropped.


2) Reverse DNS

While this is an extremely simple point, many large sites seem to neglect it. Put simply, you want the IP address of the server your mail is sent from, to resolve to the mailserver's hostname. For example, if my mailserver's IP is 123.456.123.211 and it's seen by the outside world as "mail1.mydomain.com", then you want that anybody looking up that IP address sees it resolve to "mail1.domain.com".

Ususally, you don't own your own IPs, so you can simply ask your host to setup any reverse records you require. If you do own your IPs, you must set these up at your nameservers.


3) Bounce Management

While most sites employ valid unsubscribe features, very few utilize bounce management. There are many reasons an email will bounce and many of them are not your fault. However, ISPs pay heavy attention to who manages their bounces and who doesn't. In fact, a company like Yahoo! will not grant your whitelist request unless you can demonstrate proper bounce management.

There are multiple reasons for bounces, but they generally fall into 2 categories: soft bounces and hard bounces. A soft bounce is usually a temporary problem, such as a user is over their allowed quota (their mailbox is full). Hard bounces are permanent failures, such as emailing a domain which doesn't exist.

Whether you build or buy an application to handle bounces automatically, or have someone manually handling them, this is not something that should go on ignored.

If you receive a hard bounce, you should remove/block the email address immediately. Do not send to it again. If you receive a soft bounce, how you handle it is up to you, but generally I would block an email after receiving 3+ soft bounces over a 48+ hour period.

CONTINUED IN NEXT POST...
__________________
Skype variuscr - Email varius AT gmail
Varius is offline   Share thread on Digg Share thread on Twitter Share thread on Reddit Share thread on Facebook Reply With Quote