Known Issues for Lync & Skype with Windows 10 Technical Preview Build 9879

Microsoft has released a new version of their Windows 10 Technical Preview, build number 9879 which consist of several new features:

• A new option to hide the Search or Task View buttons on the taskbar.
• Updating the new minimize and restore animations for apps.
• Replacement of the 3 dots in the Window chrome for modern apps with a “hamburger-style” icon (three lines).
• Fixed all of the crash and hang issues reported
• Windowing and gesture improvements
• New ways to use OneDrive
• Internet Explorer improvements
• Native MKV support
• Continued UI refinements

Among the new features introduced, there are also some known problems published, one of them is a known issue with Lync and Screen sharing:

• There are several known issues with screen sharing with Lync
• Skype calls will disconnect and Music will stop playing if those apps are minimized
• In some cases you may get a black screen when trying to log-in or unlock. The only option is to hold the power button to hard reboot.
• You will be unable to connect to Distributed File System network locations.
• Some systems may see disk growth of 20GB+ due to driver install duplication. On systems with low disk space this can block setup and cause a rollback to the previous build.

Source: http://blogs.windows.com/bloggingwindows/2014/11/12/new-build-available-to-the-windows-insider-program/