Microsoft is facing scrutiny over a bug in build 20026.20182 affecting classic Outlook users with Copilot features, causing the Copilot button to disappear and other functionalities to become inoperable for those with either a Copilot Chat (Basic) license or a paid M365 Copilot (Premium) account. The Copilot icon is missing from its usual locations, and while the Microsoft 365 Copilot app and web experience are functioning, users are advised to switch to Outlook on the web or the new Outlook app for immediate access. Standard troubleshooting methods have not consistently resolved the issue.