Windows Error 1721

If you are frequently installing or uninstalling programs using Windows you may have encountered the Windows Error 1721 message. This message derives from the Windows Installer Package family and will usually occur when using the Add/Remove Programs tool in Windows. The Windows Error 1721 message includes the following line:

 

“There is a problem with the Windows Installer Package. A program required for this install to complete could not be run.”

 

Most often, if you re-register the Windows Installer Service the problem will be resolved on its own. The Windows Installer Service is the tool that supervises the installation and removal of software on your computer.  The setup rules, which are centrally defined, are applied during the installation of the Windows Installer Service. When you re-register this service new rules are applied and changed. First you must unregister before you can register. The steps below have been found as the best way to re-register the Windows Installer Service. Please note that you will have to log in as the administrator after following Step 1 below.

 

1.)    Start up your computer in Safe Mode

·         When you see the Windows screen during start-up press F8 and select Safe Mode

2.)    Go to your Start Menu and select Run, type cmd.exe and click OK

3.)    Once prompted, type msiexec /unregister  and then press Enter

4.)    At the next prompt, type msiexec /reregister and press Enter

5.)    At the final prompt, type exit and press Enter to close the window

 

You may then remove or add whichever program you were previously unable to do so and restart your computer as normal.