How to Troubleshoot Error 0x80070666 When Installing Microsoft Visual C++

Many Windows users encounter the error “0x80070666” when trying to install Microsoft Visual C++, Lumberyard, or a similar distribution package. The error message usually appears at the beginning of the installation process. This problem is not specific to a particular version of Windows, as it has been confirmed to occur in Windows 7, Windows 8.1, and Windows 10.

What causes error 0x80070666 when installing Microsoft Visual C++?

The 0x80070666 error occurs often when you try to install Microsoft Visual C++, but why does this error occur? There are several different situations that can cause this error:

  • There is already another installation of Visual C++.
  • Improper installation of Visual C++.
  • Windows Update plans to install the same Visual C++ package.

How can you fix error 0x80070666? Below are some effective ways to fix it.

 

How to resolve error 0x80070666?

Checking for Windows updates

  1. To check for Windows updates, press the Windows + S key combination.
  2. Enter the keyword “update” in the search box.
  3. Click Check for updates to open the Settings tab.
  4. Then click Check for updates. Windows 10 will download the pending updates.
  5. Then you’ll need to restart Windows.

Using the install and uninstall programs troubleshooter

  1. It’s not included with Windows 10, but you can get this troubleshooter by clicking the Download button on the relevant website.
  2. Open the Troubleshooter window and click Advanced to enable the Apply repair automatically option.
  3. Click the Next option.
  4. Select the Install option.
  5. Select the Visual C++ package where error 0x80070666 occurred and click the Next button.

Uninstalling Visual C++ packages already installed

  1. Press the Windows + R key combination.
  2. Type appwiz.cpl in the Open text box and click OK to open the Windows uninstaller.
  3. Select the Microsoft Visual C++ package to uninstall.
  4. Click on the Uninstall option.
  5. Then follow the uninstall instructions to remove the software.
  6. Repeat steps three through five to uninstall all Visual C++ packages.
  7. Restart Windows after uninstalling the Visual C++ package.
  8. Then try to install the Visual C++ package for which error 0x80070666 occurs.

Frequently Asked Questions

  1. Try to restore the versions of Microsoft Visual C++ that the error message refers to.
  2. Uninstall all versions of Microsoft Visual C++ that the error message refers to.
  3. Reinstall Visual C++ by running the installer on the desktop or reinstalling the application.

  1. Download PC Repair.
  2. Install and run the application.
  3. Click the Scan Now button to find problems and anomalies.
  4. Click the Repair All button to fix the issues.

Sometimes you need to uninstall an existing version of Visual C++ Redistributable to fix problems with it. If installing the correct Visual C++ Redistributable doesn't solve your installation or repair problems, it probably means that one of the DLL files is corrupt.

Scroll down and uninstall all Microsoft Visual C++ Runtime except 2010 and 2012. Find Microsoft Visual C++ Runtime 2012 in the list of installed applications. Select this entry and click "Uninstall/Restore". The Restore, Uninstall or Cancel options will be displayed.