A. Windows Installer lets you use Group Policy to distribute software with .msi files. However, many users are unaware of .msp files, which patch .msi files. You can either execute .msp files directly on a local installation or slipstream .msp files to an installation point to automatically apply the patch to new installations. To apply patches to a software installation point, use the following command:

msiexec /a /p <.msp file and location>

This command will update the necessary files and edit the target .msi file to incorporate the patch information. After you execute this command, you need to redeploy the program you're installing so that clients receive the update. To redeploy the software, perform the following steps:

  1. Start the Microsoft Management Console (MMC) Active Directory Users and Computers snap-in (go to Start, Programs, Administrative Tools, and click Active Directory Users and Computers).
  2. Right-click the domain, organizational unit (OU), or object that has the policy that contains the deployed software, and select Properties.
  3. Select the Group Policy tab.
  4. Select the Group Policy Object (GPO) that contains the program you patched and click Edit.
  5. Expand the options to access the location at which the software is deployed.
  6. Right-click the deployed package and select All Tasks.
  7. Click Redeploy Application.
  8. Close all windows.

Clients can also trigger the reinstallation by using the following command:

msiexec /i <.msi file and location on share> REINSTALL=ALL REINSTALLMODE=vomus UPGRADEEITHRECACHE=TRUE /q