Microsoft is investigating a bug that causes Copilot issues when multiple Office apps are running simultaneously on the same system.

According to a support document published on Friday, this bug impacts Microsoft 365 customers who launch Excel, Word, PowerPoint, OneNote, Publisher, and Access on the same system.

The issue is triggered when one Office application, such as Excel, has already initiated a WebView2 instance, while another app, like Word, attempts to start a second instance.