A Microsoft .NET Framework error occurs.

Symptom:

A Microsoft .NET Framework error pop-up window appears, as shown below. 

Solution: 

1. Update Windows to the latest version. 

   1) Click the Windows "Search" button, as shown above.

   2) Enter "Windows Update" in the search box.

   3) Click "Update". 

2. Install the latest version of .NET Framework. 

• How to install .NET Framework 3.5 (includes .NET 2.0 and 3.0) on Windows 10.
• How to install .NET Framework 3.5 (includes .NET 2.0 and 3.0) on Windows 7