PKHeX error

System.TypeInitializationException: The type initializer for 'PKHeX.WinForms.Main' threw an exception. ---> System.TypeInitializationException: The type initializer for 'PKHeX.Core.GameInfo' threw an exception. ---> System.MissingMethodException: Method not found: '!!0[] System.Array.Empty()'.
   at PKHeX.Core.Util.GetStringList(String f)
   at PKHeX.Core.GameLanguage.GetStrings(String ident, String lang, String type)
   at PKHeX.Core.GameStrings..ctor(String l)
   at PKHeX.Core.GameInfo.GetStrings(Int32 index)
   at PKHeX.Core.GameInfo..cctor()
   --- End of inner exception stack trace ---
   at PKHeX.WinForms.Main..cctor()
   --- End of inner exception stack trace ---
   at PKHeX.WinForms.Main.FormLoadInitialSettings(String[] args, Boolean& showChangelog, Boolean& BAKprompt)
   at PKHeX.WinForms.Main..ctor()
   at PKHeX.WinForms.Program.Main()
System.MissingMethodException: Method not found: '!!0[] System.Array.Empty()'.
   at PKHeX.Core.Util.GetStringList(String f)
   at PKHeX.WinForms.WinFormsTranslator.GetTranslationFile(String lang)
   at PKHeX.WinForms.WinFormsTranslator.GetContext(String lang)
   at PKHeX.WinForms.ErrorWindow..ctor(String lang)
   at PKHeX.WinForms.ErrorWindow.ShowErrorDialog(String friendlyMessage, Exception ex, Boolean allowContinue)
   at PKHeX.WinForms.Program.CurrentDomain_UnhandledException(Object sender, UnhandledExceptionEventArgs e)