What should I do if the installation of VC++2015 on Win10 fails and the error "0x80070666" is reported? The Visual C++ 2015 runtime library is a commonly used software runtime library. Recently, a user failed to install VC++2015. The system prompted "Setup failed, error code is 0x80070666.", what is going on? This situation occurs because the system already contains an old version of VC++. Please see the solution below.

The prerequisite is to uninstall the old version of VC++ through programs and functions.

1. First download the "VC6.0 Junk File Cleaning Tool" (download address);

2. Unzip the downloaded compressed package;

3. Open the folder, right-click on CopyAndReg.bat, and select Run as administrator to start cleaning up some residual files of the old version of VC in the system.

4. After the cleaning is completed, restart the computer to install VC++2015 normally!

The above is the solution to the error "0x80070666" when the Win10 installation of VC++2015 fails. The method is very simple. As you can see, just download the cleaning tool introduced by the editor and run it to solve the problem perfectly.