Audit complaints
Spam complaints are the biggest cause of deliverability problems. By closely monitoring complaints reported through feedback loops, sent to the messages’ reply-to address, or sent directly to the abuse mailbox account for the ‘from addresses’ domain, marketers can isolate the source of the complaints, take corrective action, and prevent further delivery problems. Moving the unsubscribe link to the top of the message content and making it noticeable can greatly reduce the complaint rate – as much as 75%!
Test the unsubscribe link
Nothing will generate spam complaints faster than an unsubscribe link that is not functioning properly. A quick test message to a personal account can quickly check to verify that the unsubscribe process is easy and working.
Check the SPF record
Many ISPs - big and small – will use SPF (Sender Policy Framework) records to verify the mail is actually coming from who claims to be sending it. SPF records, included in the senders’ DNS, have become a key tool in preventing ‘from address’ forgery. For more information on SPF, go to http://www.openspf.org/.
To test the validity of your SPF record you can use the following site:
http://www.kitterman.com/spf/validate.html
Always verify that the SPF record includes your mailing server’s IP address. If your DNS record does not include an SPF, you can create one here:
http://old.openspf.org/wizard.html.
