Microsoft Ribbon PAB Operation Timeout

From Monday, May 18, 2026, at approximately 14:00 (UTC), to Tuesday, May 19, 2026, at approximately 15:00 (UTC), users experienced timeouts when attempting to use the Microsoft Ribbon Phish Alert Button (PAB) in Classic Outlook.

This issue was caused by an update to the PAB's authentication process that was incompatible with the Classic Outlook environment. The update used a loading method that Classic Outlook does not support, which caused the PAB to time out before it could connect to KnowBe4's servers. 

To resolve this issue, we updated how the authentication library is packaged with the PAB to ensure compatibility with Classic Outlook. The Microsoft Ribbon PAB returned to normal performance by approximately 15:00 (UTC) on May 19, 2026.

To prevent this type of issue in the future, we are updating our processes for compatibility testing and improving monitoring.

No data loss occurred as a result of this issue.