Hi,
Option 1)
Restart Visual Studio
Option 2)
Download the "Extended WPF Toolkit Binaries" (do not unblock the zip file).
Unzip the zip content.
Open the folder "Extended WPF Toolkit Binaries"
Right-click properties on "Xceed.Wpf.Toolkit.dll" and unblock this file.
Reference this "Xceed.Wpf.Toolkit.dll" in your project.
Option 3)
Reference the "Xceed.Wpf.Toolkit.dll" by installing it via "Manage Nuget Package".
――――
Get more controls, features, updates and technical support with Xceed Toolkit Plus for WPF
Option 1)
Restart Visual Studio
Option 2)
Download the "Extended WPF Toolkit Binaries" (do not unblock the zip file).
Unzip the zip content.
Open the folder "Extended WPF Toolkit Binaries"
Right-click properties on "Xceed.Wpf.Toolkit.dll" and unblock this file.
Reference this "Xceed.Wpf.Toolkit.dll" in your project.
Option 3)
Reference the "Xceed.Wpf.Toolkit.dll" by installing it via "Manage Nuget Package".
――――
Get more controls, features, updates and technical support with Xceed Toolkit Plus for WPF