Summary

Symptoms

After running an uninstall or a major upgrade (which includes an uninstall) of an MSI package, files that should have been removed are sometimes left on the target machine.

Cause

Some of the most common causes for this behavior are (a non-exhaustive list):

1. The component that the file is associated with is marked permanent.
   
2. The SharedDLL refcount is not zero after decrementing for the uninstall.
   
3. An unversioned file (i.e. TXT, HTM, etc.) has been modified since installation and an upgrade is being performed.
   
4. The component is shared with another product or feature that is still installed.

Resolution

Some known solutions for the causes above are listed below:

1. Set the Permanent property to "No" for the component containing the file.
   
2. If the file is not shared among different products, it is possible that the SharedDll refcount is no longer properly synchronized as this type of usage counting can easily become inflated. This can commonly occur on test machines with multiple installs and uninstalls during the building and testing procedure. To reset the refcount, uninstall all copies of the product and then remove the entries for the files in HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\SharedDLLs (64-Bit: HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\SharedDLLs).
3. If a file has been modified since installation, then Windows Installer assumes that it is user data and will not remove it during an upgrade. During an uninstall, this file will be removed if the containing component is uninstalled. In order to forcefully remove these files the RemoveFile table can be utilized.
   
4. This is functioning as designed and it is not recomended that the files are removed because it may break other installations.

Additional Information

The Component's settings are discussed here as seen in the Component Settings and the MSI Component Table.

For more information on logging, see the following articles:

• Q105237 HOWTO: Logging an InstallScript MSI Project (see Related KB Articles section)
  
• How to Enable Windows Installer Logging in Windows XP
  
• Description of the Setup logging options in Office 2003

If troubleshooting see, Troubleshooting Windows Installer Deployment.

Related KB Articles