Hi Moslem Zgueb
Welcome to Microsoft Q&A forum
I understand how frustrating it must be to have the shared screen and participants’ cameras turn grey consistently into a call, despite your thorough troubleshooting efforts. However, currently, we haven't received reports of this exact incident yet
To better understand the issue and identify potential causes, may I clarify a few details:
1.Are you signing in Microsoft Teams with a personal account (@hotmail, @outlook) or a business/education account (provided by a company/institution)?
2.Have you tested Teams on a different device or with a different account? If so, does the grey screen issue still occur?
3.Have you tried joining a meeting using the Teams web app (teams.microsoft.com) in a browser? Does the issue persist there?
4.Do other video conferencing apps show similar grey screen issues or is this Teams-specific?
The initial response may not fully address your needs, but it will help me better understand your situation and try to find the root causes. Thank you for your patience while we work through it
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