Bug Details and Affected Users
Microsoft has acknowledged a known issue in Teams for macOS that causes screen sharing to fail during meetings. Users may experience a blank or black screen, sharing sessions that stop unexpectedly, or an inability to start sharing at all. The problem primarily affects systems running macOS versions older than Tahoe 26.4, especially those with constrained resources like low memory or high disk usage. Organizations using Microsoft 365 Government cloud environments, including GCC, GCC High, and DoD tenants, are most impacted.
Fix Timeline and Workarounds
Microsoft originally planned to release in-product guidance by late June, but the timeline has now shifted. The guidance is expected to begin rolling out in late July 2026, with full completion targeted for mid-August 2026. Once deployed, Teams will automatically detect a sharing failure and prompt users to retry or update macOS. Until then, administrators can apply a simple workaround by enabling “Use Mac OS native sharing” in Teams settings under Screen sharing. The permanent fix is to update macOS to Tahoe 26.4 or later. Microsoft recommends that IT admins identify affected users, push macOS updates where possible, and update helpdesk documentation to cover the symptoms and available solutions.
Source: Cyber Security News
