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When screen sharing people see black screen
Hi, I had Thinkpad laptop and was using additional monitor on and off without any issues and suddenly since 2-3 weeks, when I am trying to share my screen, people are just seeing black screen. This ...
Hi Viren_Manek;
Believe is ISP related.
Change the QoS setting in Teams fixed the problems for us.
Your tenant admin needs to change this:
Teams Admin> Meetings > Meeting Settings > Network
Turn off -> Insert Quality of Service (QoS) markers for real-time media traffic
Also update Teams client to the latest version.
Log-out and log back in.
Restart your Teams app.
You may need to wait for the change to kick in.
Good luck.
Regards
Tenny
Adriana_001 update overnight is that my issue has now been fixed - I can share my screen in Team while using the Huawei modem. I have no idea who and what was done. A bit concerning when I don't know what happened / what was done to resolve the issue.
Just tested mine with real hope. Alas, I was disappointed. Still not working for me (Mid North Coast, NSW, Australia)
- I had similar issue - difference in my case was that the problem of black screen share and stuck video, was a problem on wired ethernet connection only. Wi-Fi was fine but I as a network engineer I wanted to understand the problem.
Anyhow, I still don’t know what the root cause although it appears QoS related.
The fix that worked for me:
- on your router block your LAN traffic ( source) going to internet on port 3479,3480 and 3481 destination
- in other words - block Lan Traffic source ; destination internet and destination ports: 3479,3480 and 3481.
I believe this forces mSTeams traffic to go via port 443 which is what the web version uses.
I hope it works for you.
