Email Security.Cloud: Email Delivery Issue to Yahoo Domains

We have monitored the service for stability and this incident shall now be closed.

We have received confirmation from the Yahoo team that the previously applied throttling has been removed. The remaining queued emails are successfully delivering as per the retry schedule. We are closely monitoring the email service and will provide updates as new information becomes available.

The majority of previously queued emails have delivered and the remaining continue to attempt delivery as per retry schedule. We are still seeing rate-limiting applied by Yahoo and we continue to wait for their response regarding the throttled connections. A subset of our EU West infrastructure remains out of service and there is no impact to email delivery for any new emails.

We will provide updates as soon as new information is available.

We are continuing to see emails queued on the Broadcom infrastructure delivering but at a slow rate. We are actively engaging with Yahoo team and have requested throttling to be removed.

We will provide updates as soon as new information is available.

Our investigation shows the issue is occurring due to Yahoo rate-limiting our EMEA-West IP range. We are seeing emails queued on the Broadcom infrastructure delivering but at a slow rate. In addition, we are trying to connect with Yahoo team in order for throttling to be removed.

Note that majority of EMEA infrastructure is fully operational and email scanning/delivery is operating as normal. We will provide updates as soon as new information is available.

We are aware of a small subset of customers experiencing delays sending emails to Yahoo domain addresses. The result is that emails processed by a subset of our EMEA infrastructure are queued for delivery. As this is only impacting a subset of our EMEA infrastructure, we have gone ahead and taken the impacted infrastructure out of service and new emails are no longer impacted. Any existing email will remain queued on our infrastructure till the issue is resolved.

Please note that there is no impact to protection services, and all other aspects of our services remain functional. We will provide updates as soon as new information is available.