Microsoft Teams - Black screen when sharing desktop, works with single application

I hate it, I just hate the microsoft development team that loves to mess up our lives with these problems. I click on the teams sharing tray installed on windows and it just does nothing, it reduces the screen to the side corner as if it were sharing my screen but nothing is actually being shared. if i join teams on google chrome the sharing happens normally. The worst are these crazy solutions that the pseudo technicians put on the forums. I have reinstalled from scratch, I have already cleared the cache, I am almost setting my computer on fire.

Yeah, I did it live too... a strange thing is that sharing the entire desktop @3440 x 1440 was for sure working fine 3 weeks ago, so seems a regression introduced in recent Teams updates.

Hello Ankita,

If you find any solution for Treawlony1986 can you please share it with the community because I have exactly the same issue. I own a QHD 21:9 monitor and I'm not able to share the entire desktop as for on the other side is displayed a black screen.

If while sharing the entire desktop I change the external monitor resolution from 3440 x 1440 to 2560 x 1440 the screen sharing starts working, going back to 3440 x 1440 it is black again.

Thanks

Regards

Hi Shadow,

that's interesting: we could not solve the issue, but following your input I tried to change the resolution from 3440*1440 to 2560*1080 and it actually worked! then changing back to the original resolution it stopped working again.

Also, I did it "live" during the screen sharing and it was working directly after the resolution change.

@Ankita, does this help something on the resolution?

Following you input, I found this with other with the same issue:

https://microsoftteams.uservoice.com/forums/555103-public/suggestions/39696394-screen-sharing-with-3440-x-1440-resolution-shows-a

Hi Ankita,

I will run the debug, permission to share the screens are ok.

I just noticed something else: currently I'm connected with my surface laptop on my 21:9 widescreen monitor, lid closed (with Surface Dock).

Opening the lid, laptop screen get shared, but still nothing on secondary monitor.

then I tested the following:

• Sharing an application was working fine
• I've opened the application full-screen, shared the application and got black screen again
• I've then shared a windowed application and expanded to full screen, and was working fine.

Looks like somehow Teams is not able to digest anymore a full-sized screen sharing from a 21:9 monitor (thing that it was able to do since couple days ago).

Just checking windows update, closest update i've got (not considering windows defender) was on the 13 of FEbruary the security update KB4524244. But it was working fine those days.