.NET deployment will not uninstall without repairing first

public override void Install(System.Collections.IDictionary stateSaver)
        {
            base.Install(stateSaver);
 
            RegistrationConfig rc = new RegistrationConfig();
            rc.AssemblyFile = GetType().Assembly.Location;
            rc.ApplicationRootDirectory = System.IO.Path.GetDirectoryName(Context.Parameters["assemblypath"]);
            rc.InstallationFlags = InstallationFlags.FindOrCreateTargetApplication;
            RegistrationHelper regHelper = new RegistrationHelper();
            regHelper.InstallAssemblyFromConfig(ref rc);
 
            // Save the state - you will need this for the uninstall
            stateSaver.Add("AppID", rc.Application);
            stateSaver.Add("Assembly", rc.AssemblyFile);
        }
 
        public override void Uninstall(System.Collections.IDictionary savedState)
        {
            if (savedState == null)
                throw new ArgumentNullException("savedState", "Saved State is required to uninstall this application, please repair and try again");
 
            base.Uninstall(savedState);
 
            // Get the state created when the app was installed
            string appID = (string)savedState["AppID"];
            string assembly = (string)savedState["Assembly"];
            // Uninstall the application
            RegistrationHelper regHelper = new RegistrationHelper();
            regHelper.UninstallAssembly(assembly, appID);
 
        }