Teams: Audio, Video or Screen‑Share Not Working

Category: Microsoft 365 · Audience: Customers & Technicians · Est. time: 10–20 min

Summary

Most Teams call problems are device selection, permissions, or a cached client. Work through in order before a call.

Symptoms

• Others can't hear you, or you can't hear them
• Camera shows black / "no camera"
• Screen‑share button greyed out or the share is black

Solution

1. Pick the right devices. In Teams: ⋯ (Settings and more) → Settings → Devices. Set the correct Speaker, Microphone, and Camera, then use Make a test call.
2. Check OS permissions (Windows). Settings → Privacy & security → Microphone / Camera → ensure access is On and Microsoft Teams is allowed. On macOS: System Settings → Privacy & Security → Microphone / Camera / Screen Recording → enable Teams.
3. Close apps holding the camera/mic. Only one app can use them at a time — close Zoom, the Camera app, other browser tabs.
4. Screen‑share greyed out or black: on macOS you must grant Screen Recording permission (then quit and reopen Teams). On Windows, update the graphics driver if the shared screen is black.
5. Leave and rejoin the meeting. A quick rejoin re‑negotiates audio/video and fixes many one‑off glitches.
6. Clear the Teams cache (Technician).

• New Teams: Settings → ... → Settings → General → "Clear cache/Reset."
• Classic Teams (Windows): quit Teams, then delete the contents of %appdata%\Microsoft\Teams, and reopen.

1. Update or reinstall Teams. Ensure the latest version; reinstall if audio/video is persistently broken.

If that doesn't work

• Test the headset/webcam in another app (Camera app / Zoom) to isolate hardware vs Teams.
• Try Teams on the web (teams.microsoft.com) — if it works there, it's the desktop client.
• Escalate to BBN Support with the device names and whether the test call works.

Prevention

• After Windows/macOS or Teams updates, re‑check mic/camera permissions before an important call.