The tag 'TimePicker' does not exist in XML namespace 'http://schemas.xceed.com/wpf/xaml/toolkit' in my WPF application

[PMichael1966]

Getting error.. The tag 'TimePicker' does not exist in XML namespace 'http://schemas.xceed.com/wpf/xaml/toolkit' in my WPF application when building with MSBuild. I get no error when build with VS 2019 .netframework 4.8

[tvle]

@PMichael1966 - I faced the same error trying to upgrade to the latest version and discovered that I needed to install the Nuget package in all of the projects in my solution that referenced the component I was using from the toolkit. The really old version of the Xceed.Wpf.Toolkit package I was using (2.0.0) built fine using VS or MSBuild (from an ADO pipeline build) with only one of the projects in my solution referencing the package. Hope that helps you if you are still facing this issue.