How to enable friendly trees in Windows Explorer
Contributed by shamanstears 
August 2, 2006 
Tagged: Windows networking
Friendly trees enable automatic folder expansion when you select a disk, and any other expanded disks will collapse giving a cleaner view.
1. Start the registry editor (regedit.exe).
2. Navigate to the HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced registry subkey.
3. Double click the “FriendlyTree” value (or create the DWORD type value if it doesn’t exist).
4. Set the value to 1 to enable the feature or 0 to disable it.
5. Click OK and close the registry editor.