In this article, Stefan Pollard offers a list of things to start with when you are called in to fix a failing email marketing program:

1. Authentication. This is your first stop. Check your SPF, SenderID, and DomainKeys records to make sure they're accurate and up to date. Can ISPs verify you are who you claim to be and have the right to send messages from your IP address? While you're at it, check the rest of your basic DNS entries for accuracy and completeness. Even something as simple as a failed rDNS check can cause delivery challenges.
   
   
2. Delivery challenges. Look for blocks, bottlenecks, and other issues related to sending messages and receiving them correctly. Get on ISP whitelists, and join their feedback loops to hear about and resolve spam complaints.
   
   
3. List hygiene. Your list software should automatically remove any invalid addresses. Ensure this function works correctly and keep your list clean. Look for inactive accounts (those that haven't opened or clicked in over three to six months), and use reactivation and purge strategies to keep your list small and highly responsive.
   
   
4. Address collection. Find out all you can about how your predecessors acquired the addresses in your database, especially if anyone bought or rented lists with murky permission histories. If you can't verify permission for an address, you might have to ask the owner to verify permission or, in the worst case, scrap it to avoid any chance it's a spam trap address that could cause blocking problems. Upgrade your permission level to confirm opt-ins.
   
   
5. Expectation setting. Look at what your program promises to e-mail: content, frequency, format, and the like, then see what it delivers. Is there a difference? Be specific about what you'll send and how often. Use a preference page to let subscribers tailor a program that meets their own content, format, and frequency needs. If you have to repermission addresses on your list, you can make it a more valuable prospect by inviting subscribers to do this or to unsubscribe.
   
   
6. Reputation management. If the e-mail program you inherited is pretty much in tatters, you'll have to spend time repairing your sender reputation, both with your own recipients and the ISPs you send to. You took the first steps when you authenticated. Now, you have to patrol every mailbox associated with your e-mail program where someone could reply with a comment, request, or complaint and deal with those immediately. Your goal is to reduce spam complaints to a level below 0.1 percent per domain.
   
   
7. Design and rendering. Assuming you resolved technical issues, you can now attack how messages appear to the recipient. Clear up bad or incompatible HTML code, end the reliance on a single large image, and see how the message appears when images are blocked or the message is viewed in different browsers and on different equipment, such as a PDA or cell phone.
   
   
8. Segmentation and relevance. Here's where you deliver on the expectations set at opt-in. Honor those expectations and avoid cross-promoting unless the material warrants it.
   
   
9. Landing pages. Yes, these are part of an e-mail campaign and require as much thought and testing as the message itself. E-mail gets subscribers back to your site. Make sure the page where they land puts them right where they need to be. Don't force them to hunt around.

Source: ClickZ