Y2K22 Bug That Crippled Microsoft’s Email Delivery Service

Microsoft fixes a date validation error that caused emails to get stuck on its Exchange Servers.

This issue is not as security-related attack, but rather a disruption cased by an error on Microsoft’s end.

What has happened?

Your business might have (knowingly or unknowingly) experienced some email disruptions where emails were stuck in a transport que. This was because of a date validation error. Microsoft noted that the issue was caused due to a date issue in a signature file used by the malware scanning engine within Exchange Server. To learn more technical details here is the original Microsoft article on the issue.

What can I do?

To help fix this Y2K22 issue Microsoft is recommending customers to download a PowerShell-based scan engine reset script that can then be executed on each Exchange mailbox server used for downloading antimalware updates. It’s worth noting that the update will also change the version of the engine to the newest version.

If you need any help or support, you can always reach out to Britec and contact us.