Hi @Craig Parsons,
Welcome to Microsoft Q&A forum.
Thank you for reaching out and sharing your experience when Teams is prevented from using the camera and microphone and your previous work account shows up when joining a Teams meeting even after your system admin has attempted to delete every work account. I can totally understand how disruptive it is to be not able to use your designated account for your Teams meeting and use camera and microphone during the meeting.
To better understand the issue and assist you with targeted solutions, could you please share the following information:
- Which device and operating system are you using (Windows, macOS, iOS, Android)?
- How are you joining the meeting: Teams desktop app, Teams on the web (Edge or Chrome), or mobile app?
- Are you working directly on your PC, or through Remote Desktop or a virtual desktop (VDI)?
- Are you using a built in camera and mic, or an external webcam and headset (USB or Bluetooth)?
In the meantime, if you are using Windows on the Teams desktop app, please try these steps.
- Close anything that could be using the camera or microphone (Zoom, Skype, browser tabs with video, the Windows Camera app), then restart your device.
- Check Windows permissions
- Open Settings, then Privacy & security.
- Select Camera and turn on Camera access and Let desktop apps access your camera.

- Select Microphone and turn on Microphone access and Let desktop apps access your microphone.

- Check device selection inside Teams
- Open Teams, select more (...), then Settings.
- Select Devices.
- Confirm the correct Camera and Microphone are selected. Run Make a test call to validate.

- Reset Teams app
- Go to device settings, select Apps > Installed apps, and then type Microsoft Teams in the search box.
- Locate the New Microsoft Teams app from the results, select the More options button (...) on the right, and then select Advanced options.
- In the Reset section, select Reset.

- Clear cached credentials in Credential Manager
Sometimes outdated or corrupted cached credentials can cause old work account to show up.
- Open Control Panel
- Go to Credential Manager
- Select Windows Credentials
- Remove any entries related to:
- Microsoft Teams
- Microsoft Office
- Microsoft 365
- ADAL / MSAL / MicrosoftAccount

- Restart the device and sign back into Teams.
I hope this information is helpful. Please follow the steps above and let me know if it works for you. If not, we can continue working together to resolve the issue.
Thank you for your patience and understanding. If you have any questions or need additional assistance, please don’t hesitate to reach out so I can continue to support you. If you found the response useful, please consider marking it as accepted, as this may help other community members who are looking for similar guidance.
I look forward to continuing the conversation.
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