Lync owas windows 8_1 bug

** UPDATE **
The bug has been fixed in the following update:
You might have to break the farm, and recreate it after the update.

There is a known bug affecting windows 8.1 users when they try to present a PowerPoint presentation in any meeting. If you have installed any version of Windows 8.1 and tried it, you might have seen the all too familiar screen:

If you have tried to debug the error, you might be as frustrated as me, because there is (at least I was not able to find any) no visible error on any server or client component. Even a Fiddler trace revealed nothing but 200 OK messages.

This bug is not present in Lync Online, and I hope we'll see a bugfix for the onprem installations as well soon.

In the meantime, do as I did to correct the error. Join your meeting through the web browser, appending ?sl=2 to your meet url. At least I was able to run the presentation through my webapp.

Hope this helps, and that we see a bugfix soon :)