errorcode as follows.

System.InvalidOperationException: An error occurred while trying to create the form. See Exception.InnerException more information. Error: An exception is throw in constructor calls for 'GameBrowser.PlayBrowser' format that matches the specified binding constraints. ---> System.Windows.Markup.XamlParseException: now throw an exception in the constructor call to 'GameBrowser.PlayBrowser' format that matches the specified binding constraints. ---> System.ArgumentException: The item with the same key has already been added.
   Location: System.ThrowHelper.ThrowArgumentException (ExceptionResource resource)
   Location: System.Collections.Generic.Dictionary2.Insert (TKey key, TValue value, Boolean add)    Location: System.Collections.ObjectModel.KeyedCollection2.AddKey (TKey key, TItem item)
   Location: System.Collections.ObjectModel.KeyedCollection2.InsertItem (Int32 index, TItem item)    Location: System.Collections.ObjectModel.Collection1.Add (T item)
   Location: GameBrowser.RecentItems.LoadRecentList ()
   Location: GameBrowser.RecentItems..ctor (String listName)
   Location: GameBrowser.PlayBrowser..ctor ()
   --- End of inner exception stack trace ---
   Location: System.Windows.Markup.XamlReader.RewrapException (Exception e, IXamlLineInfo lineInfo, Uri baseUri)
   Location: System.Windows.Markup.WpfXamlLoader.Load (XamlReader xamlReader, IXamlObjectWriterFactory writerFactory, Boolean skipJournaledProperties, Object rootObject, XamlObjectWriterSettings settings, Uri baseUri)
   Location: System.Windows.Markup.WpfXamlLoader.LoadBaml (XamlReader xamlReader, Boolean skipJournaledProperties, Object rootObject, XamlAccessLevel accessLevel, Uri baseUri)
   Location: System.Windows.Markup.XamlReader.LoadBaml (Stream stream, ParserContext parserContext, Object parent, Boolean closeStream)
   Location: System.Windows.Application.LoadComponent (Object component, Uri resourceLocator)
   Location: GameBrowser.Launcher.InitializeComponent ()
   Location: GameBrowser.Launcher..ctor ()
   Location: TextAdventures.Quest.Main.InitializeComponent ()
   Location: TextAdventures.Quest.Main..ctor ()
   --- End of inner exception stack trace ---
   Location: TextAdventures.Quest.My.MyProject.MyForms.Create__Instance __ [T] (T Instance)
   Location: TextAdventures.Quest.My.MyApplication.OnCreateMainForm ()
   Location: Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.OnRun ()
   Location: Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.DoApplicationModel ()

it happens after i installed steam and played some games. but even after uninstalling steam and its games, this still happens. can someone help me out?