Randy Cook gives us some vital info about how SVS interacts with the Windows Registry. If you're faced with editing the registry of a virtualized app (shudder) this tip could be a life saver.
If you come to a point in life when you need to tweak the Registry of a virtualized application, you'll want to keep this explanation of how SVS works with registry keys within reach.
The HKEY_CLASSES_ROOT key is a virtual key that Windows creates by combining the data from HKEY_CURRENT_USER\Software\Classes and HKEY_LOCAL_MACHINE\Software\Classes. When there is a conflict in this data, preference is given to the data contained in HKEY_CURRENT_USER\Software\Classes.
SVS does not store data in the virtual HKEY_CLASSES_ROOT key. Instead it stores it in its real location under either HKEY_CURRENT_USER\Software\Classes or HKEY_LOCAL_MACHINE\Software\Classes. At runtime, Windows reads the SVS data for active layers from these locations and properly renders HKEY_CLASSES_ROOT....