Home › Speed Up My Computer › Find Lost Hard Drive Space

The Installer Directory

The Installer directory is a required directory used by the Windows Installer service. This directory contains the data necessary to update and remove the programs that have been installed with the Windows Installer. Over time this directory can become cluttered with unnecessary data that has been left behind by previously removed programs or programs that did not install correctly. Thankfully Microsoft provides a tool that you can use to safely remove junk from this folder (Only works on Windows XP / NT).

Warning: Misuse of this tool will have unpredictable results.

  1. Download and install the Windows Installer Cleanup utility.
  2. Open a Command Prompt. (Click Start -> Run -> Type CMD and press Enter)
  3. Type cd\"Program Files"\"Windows Installer Clean up" (include quotes)
    NOTE: Directory location may be different on you computer.
  4. Type msizap G! and press enter. Note: This command should only be preformed on Windows XP / NT.