Disable search history for Windows Explorer in Windows 7
Windows Explorer in Windows 7 will remember your previous file searches. When typing in a new search, then it will perform auto-suggest using the previous searches.
It is possible to clear a previous file search by hovering over the suggestion in the search-box, and pressing the delete-key.
Turn off the search history feature by setting this DWORD value:
[HKEY_CURRENT_USER \Software \Policies \Microsoft \Windows \Explorer]
DisableSearchBoxSuggestions = 1
This should match the group policy “Turn off display of recent search entries in the Windows Explorer search box” (User Configuration Administrative Templates Windows Components Windows Explorer)
Clear all cached search history entries by deleting the WordWheelQuery branch:
[HKEY_CURRENT_USER \Software \Microsoft \Windows \CurrentVersion \Explorer \WordWheelQuery]
Credits WinHelpOnline