Resolve Vista Error 1721

In this article we will discuss how to resolve error 1721 that you may experience while installing programs on your Windows Vista computer. We will also discuss when to do a force uninstall of a program.

Issue

When you try to install a program on a Microsoft Windows Vista computer and the installation fails, you may receive the error 1721 message stating, “a program required for the install to complete could not be run”

Resolution

To fix the vista error 1721, reregister the Windows Installer Service. If the error persists, download and install Windows Installer Cleanup Utility and use it to remove any entry of the program that you failed to install.

Task 1 – Reregister the Windows Installer Service

On a Windows computer, the Windows Installer Service does the job of managing the uninstallation and installation of programs. To perform these tasks, the Windows Installer Service uses the Microsoft installation engine. In case the entries corresponding to the Microsoft engine are incorrect or corrupt, you may not be able to install programs.

To reregister the Windows Installer, perform the following steps:

  1. Click Start, click All Programs, click Accessories, right-click Command Prompt, and click Run as Administrator.
  2. Type the administrator password when prompted.
  3. At command prompt type the following command and press Enter –

    4. %windir%\system32\msiexec /unregserver

  4. Next, at command prompt type the following command and press Enter –

    5. %windir%\system32\msiexec /regserver

  5. Type exit and press enter to close command prompt.

Note: %windir% is a variable that refers to the drive on which Windows is installed. By default, in Windows Vista it is the C: drive.

After you have reregistered the Windows Installer Service, try to install the program. If the installation fails again and you receive the error, proceed to task 2.

Task 2 – Install Windows Installer Cleanup Utility

Download and install Windows Installer Cleanup Utility and remove any entry of the program that you are unable to install.

To achieve this, perform the following steps:

  1. Download the Windows Installer Cleanup utility from the Microsoft website.
  2. Save the file msicuu2.exe on your desktop.
  3. Double-click msicuu2.exe and click Run. This will start the installation of the Windows Installer Cleanup Utility.
  4. Follow the on-screen instructions and click the Finish button when the installation completes.
  5. Click Start, point to All Programs, and then click Windows Install Clean Up.
  6. In the Windows Installer Clean Up dialog box, locate the program entry, and click the Remove button.
  7. Click OK when a warning box appears.
  8. Wait for the uninstallation to complete, then click Exit to close the Windows Installer Clean Up dialog box.

After you have removed the program entry, try to install the program.

I’m unable to uninstall a program using Add or Remove Programs. What should I do?

At times, when some core program files are damaged, you may not be able to uninstall the program using the built-in Add or Remove Programs utility. In such cases, it is recommended that you use a reliable third-party uninstaller tool, such as Perfect Uninstaller to do a force uninstall of the problem software.