Deferred emails to Prodigy-protected and Rackspace-hosted domains

Deferrals of emails have slowed substantially but have not ceased altogether. Deferrals to certain email service providers will always occur due to several factors, including domain and sender reputations. Mailprotector deems the IP reputation problem resolved at this time. Mailprotector does not control domain and sender reputations. IP reputation management is influenced by Mailprotector's sending infrastructure management, but it is not solely in our control.

Deferrals may happen on occasion. Users will see a deferral notice under the right circumstances as we continue to manage the sending infrastructure to build additional resilience and strictly enforce the sending policy.

If a deferral or bounce is questionable, please open a support request, and Partner Success will gladly explain the situation as best as possible. In a pinch, the option is to send emails directly from the email service provider rather than CloudFilter's smarthost relay.

Mailprotector has observed improved deliverability to Rackspace and AT&T domains. However, we are cautious, given that email volume is typically reduced between the Christmas and New Year's Day holidays.

Over the coming weeks, we will move affected servers back into full production and wait for stabilized delivery responses. We expect some deferrals because these email service providers do not offer a means to set an expected volume of emails. We cannot eliminate deferrals entirely, especially if an email is considered questionable for spam or malicious intent.

If the process moves forward smoothly and as expected, we will send one more update in a couple of weeks. We hope to consider this incident complete.

Mailprotector resolved a significant reputation issue that affected AT&T and Yahoo domains. As part of that remediation, the volume of emails from affected servers significantly dropped. As the affected servers have been put back into service, some domains using Prodigy (part of AT&T and Yahoo) and Rackspace are deferring email delivery due to the rapid volume change. Mailprotector is mitigating the occurrence of deferrals by metering the volume of affected servers. This process will take several more weeks to reach full resolution.