Every effort is made to ensure that legitimate emails are not falsely identified as spam ("false-positives"). The Cloudmark system is able to automatically self-correct, therefore reducing incidents of false positives as well as false negatives. Reporters can provide feedback on a missed spam message or on a legitimate message which has been misclassified as spam. Once this feedback is corroborated, the message is automatically re-classified. In addition, Cloudmark's system factors in reputation data from leading reputation services providers Return Path and Habeas.
ReturnPath's Sender Score system provides us with access to a comprehensive email reputation database. The data is compiled from more than 40 million mailboxes across a number of email providers, including KD Interactive Hosted Email. Sender Score looks at things such as complaint data, mail volume, bounced messages, unsubscribe functionality, security practices, identity stability, and more. Think of it as a credit score for email senders. When an email arrives, particularly bulk mail, we are able to tell if the sender is a "good" sender or a "bad" sender.
While every effort is made to ensure that legitimate emails are not identified as spam, a small number of false-positives are unavoidable. To solve this problem, domain administrators and email users can specify trusted email addresses, domain names, and mail server IP addresses that should always bypass the spam filtering system. This feature should be used when specific emails sometimes get identified as spam, such as opt-in newsletters or emails from colleagues whose mail servers are blacklisted or configured improperly.
KD Interactive Hosted Email also maintains a system-wide safelist. This list tracks mail servers run by large companies such as IBM, FedEx, and Paypal, as well as popular discussion lists such as those hosted by SourceForge.net and Yahoo Groups.
When you send an email to other people at your company, you obviously do not want it to be blocked as spam. Therefore, whenever our customers send mail from our servers, that mail automatically bypasses the spam filtering system. This ensures that internal mail will be delivered reliably.