 Windows Installer Zapper (msizap.exe, a command-line tool) and Windows Installer CleanUp Utility (Msicuu.exe, a GUI tool) are tools for cleaning Windows Installer databases in Microsoft Windows.Many of the Windows Resource Kit tools are included as part of the Support Tools.Although no x64 Resource Kit tools have been produced by Microsoft, some support tools are available in native x64 versions on the Windows XP Professional x64 and Windows Server 2003 x64 Editions CDs.