Starting on January 11, 2024, we observed an unusual increase in blocked bounceback email error messages on some linode.com email domains. Additionally, Compute Support saw an increase in customer inquiries regarding Microsoft email services, such as outlook.com, hotmail.com, and msn.com, where users were unable to receive emails from linode.com domains due to a technical impediment.
Despite our initial attempts to resolve the issue with Microsoft, we encountered communication hurdles in the process. Efforts were made to escalate the matter, and eventually, measures were taken to address the technical issue. This allowed emails to be delivered successfully.
Ongoing discussions with Microsoft aim to unravel the root cause of this situation and to implement preventive measures for similar incidents in the future. Furthermore, we are proactively exploring strategies outside of those conversations to mitigate the likelihood of such issues from reoccurring.