Skype for Business meeting displays black screen and pause icon

[Joe Cistaro]

Hello,

I received a notice from a user in our Enterprise.  She is connecting to a meeting and the following is displayed when the presenter tries to share her screen.  Look familiar to anyone?  What should I be looking at to resolve?

Thanks!

Joe

[#2]

Joe,

I have not seen that yet. Curious, is this Windows 10, 7, or other? What version of S4B? Is it doing this to all conferences she attends or only this one person?

John

[#3]

Operating system

Windows 10.0.14393 SP: 0.0 Type: 1(Workstation) Suite: 256 Arch: x64 WOW64: True

User agent

UCCAPI/16.0.4639.1000 OC/16.0.4639.1000 (Skype for Business)

At this I know about only on conference.  This was just reported to me moments ago.  I'll be doing some troubleshooting and opening a case with MS to see what is happening here.

[#4]

We are still on Windows 7, but matches the S4B version. I would be curious to know if other meetings do the same or only for the one person or contact. I have not seen this happen on our Windows 7 connection. I have connected via Windows 10 at home and do not recall seeing this either, but it has been a little while since I connected on Windows 10 to S4B.

John

[#5]

Anyone figure this out?! This is killing us.

It appears to only happen in a peer to peer scenario, or at least mostly. Tried several different versions of S4B. We're actively seeing the client trying to share content respond with a reset packet. So something on the client is actively doing this.

Thanks!!!

[#6]

Checked Windows 10 with S4B and did not see the issue. Not sure if this helps, but someone talking in 2016 of a similar issue. You might already found this solution:

https://social.technet.microsoft.com/Forums/en-US/19b93a29-5551-4334-b5ca-321296ed9a43/black-screen-...

Guessing it might have been a Windows update that caused the issue. We have had that happen a few times with Office products where something is working fine, updates are applied, and then stops working. If you can target the date when it stopped working and see if maybe updates were applied to see if you can figure out which update caused the issue might be worth checking.

John

[#7]

Is this person a presenter in the meeting or a attendee?

[#8 · Accepted solution]

So, we ended finally found this https://support.microsoft.com/en-us/help/3150900/black-or-frozen-screen-when-you-share-your-screen-i... We don't know how or when but several of our users had that registry key. When a user w/out that key was initiating a screen share it would pause (black screen with white pause icon in top left). If a user with those registry keys initiated the screen sharing it works because those w/out the reg key would I guess "fall back" to RDP protocol. So we're working on collecting all machines in our firm that have that registry key and removing.

[#9]

Ah, didn't see your reply until today. Yup, it was those registry keys for us too.

[#10]

Glad to hear you got it figured out. What is odd that the registry keys were changed and started causing the issue.

John

[#11]

Ya, that's the head scratcher. We did some further testing too using the scrub vbs files for 15 and 16 to see if those keys would go away. They remain even after running the Microsoft office scrub vbs and me manually uninstalling every Microsoft Office product. The HKUM 16.0 key was left behind with the P2P override key in place. So we're going to be writing a ps script to check for it and delete it on all machines. Or we're thinking of just pushing out a deployment of Office to all machines and adding a task to purge the Office reg key all together for all machines. Wipe the slate clean.

Creighton

[#12]

That is odd! Yeah, at least it gives something to check instead of just the blank screen. We have more and more of our customers starting to use S4B for conferences, so good to know about this happening in case we get reports about it. I did not check for the registry key, but guessing we probably have it too.

John

[#13]

We've been on S4B and used it as our primary content and sharing platform for 3+ years now. This didn't start till the RDP to VBSS protocol apparently. Otherwise we've never had any issues. We also just left O365 to a hosted solution to get all of the PBX features we need as we wanted Skype to be our pbx as well. Soon as that contract is up we'll migrate back when there is feature parity.

[#14]

We struggled with this for quite some time.  We opened at least two tickets for this with MS, and we always were give the keys referenced in this thread.  It turns out that a new ticket with MS revealed that we need to add more keys to disable VBSS in conferences.  The keys we had been given disabled VBSS in P2P conversations, the new keys disable VBSS in conferences:

[HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Lync]

"EnableConferenceScreenSharingOverVideo"=dword:00000000

Additionally, if you use the 32-bit version of Skype for Business 2016 on a 64-bit operating system, add the following subkey:

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\16.0\Lync]

"EnableConferenceScreenSharingOverVideo"=dword:00000000

Deploying these keys and hoping that this is the end of this.  Although I am trying to get the MSI codebase fixed to be able to use VBSS reliably rather than having to hack the registry to revert to RDP (not holding breath).

@Joe Cistaro