This month, one of Microsoft's released Patch Tuesday updates (KB2984972) caused some App-V delivered packages to fail. The app would indicate that it was launching, but either stop responding or just not continue starting at all.
After the release and subsequent installation, this was one of the immediately hot issue for many customers. Today, Microsoft has finally communicated a fix, which required Windows registry modifications.
The fix is located in the updated support article (KB2984972). The registry modifications are different depending on which version of App-V (5.0 or 4.6) you are using.
KB2984972 has also been reported to break Wyse thin clients running multi-monitor setups. This problem can be fixed by updated the Wyse thin client firmware.