I am having an issue where my right click / context menu is automatically closing after being opened while using Windows 8.1 x64 Professional, but only on one of my machines currently running Windows 8.

I can reproduce the issue relatively reliably (maybe 50-70% of the time) on the problem machine by taking these steps:

1. Select an item (file, directory, etc) inside Windows Explorer
2. Left click another item, selecting it
3. Very quickly (very small fraction of second, but clearly after the left click has been released), right click, opening the Context Menu
4. The context menu will close automatically after another fraction of a second

Another item I noticed is that the ribbon will update to match the new file type (assuming a new file type is selected) at the same time that the context menu is closed.

I have all non-windows shell extensions disabled through nirsoft's shellexview (including the explorer.exe or full windows restart after making changes), and I am thoroughly stumped as to why this might be happening. Any other suggestions / thoughts? Is there possibly something invalid with my HKEY_CLASSES_ROOT keys which may be causing this?