After installing the WPF software I was not able to open any project in VS 2017 without it hanging.

 

In the end I removed the VS integration and was able to resume development.

 

It was the only Telerik component I had installed. I can't find the version number but it was the latest of the website as of 17th Oct 2019.

 

Can you explain why this happened?

An error occurred while running the wizard.

Error executing custom action Telerik.Windows.WPF.VSX.Actions.UpdateReferencesAction: System.Runtime.InteropServices.COMException (0x80004005): This reference cannot be removed from the project because it is always referenced by the compiler.
   at VSLangProj.Reference.Remove()
   at Telerik.VSX.Internal.ProjectManagement.ApplicationProjectAssemblyReference.RemoveReference()
   at Telerik.VSX.ProjectConfigurators.ApplicationReferenceManager.RemoveReferences()
   at Telerik.VSX.ProjectConfigurators.ApplicationReferenceManager.UpdateReferences()
   at Telerik.VSX.Actions.UpdateReferencesAction.UpdateReferences(IProjectWrapUIComponents projectWrap)
   at Telerik.VSX.Actions.UpdateReferencesAction.Execute(WizardContext wizardContext, IPropertyDataDictionary arguments, IProjectWrap project)
   at Telerik.VSX.Actions.ProjectActionBase.Execute(WizardContext wizardContext, IPropertyDataDictionary arguments)
   at Telerik.VSX.WizardEngine.Actions.ActionBase.Telerik.WizardFramework.IAction.Execute(IWizardContext wizardContext, IPropertyDataDictionary arguments)
   at Telerik.VSX.WizardEngine.ActionManager.ExecActions()