WebView InvokeScript HRESULT 0x80020101

I'm trying to invoke a function in a WebView. Some target functions I need to call are these: ``` play: function() { if (this.value < this.p.max) { this.inc(); this.timer = new it_timer({ object: this, method: "play", timeout: 200 }); } else this.stop(); }, stop: function() { if (this.timer) this.timer.stop(); this.playing = false; this.playbutton.style.backgroundPosition = "0 0"; } ``` I started by calling ``` webView.InvokeScript("play", new string[0]); ``` but that didn't work, HRESULT: 0x80020101. I found this http://support.microsoft.com/kb/247784 on the topic, but it didn't help me at all. I then tried to do what I found as an example on multiple sites: ``` webView.InvokeScript("eval", new string[] { "document.documentElement.outerHTML;"); ``` and ``` webView.InvokeScript("alert", new string[] {"message"}); ``` but both of those didn't work, giving the same HRESULT code. The WebView renders normally and javascript works fine on the page. I'd appreciate any help in identifying the problem / finding a solution. EDIT: It seems "alert" and all methods which are declared in classes don't work. There seems to have been an InvokeMethod(..) in earlier .NET Versions, are there any alternatives for WinRT?