Exception- Unable to get window handle for WebBrowser Control

Hi,

I am using webbrowser control in C# as HtmlEditor. And calling that webbrowser in Wpf window form host. My html pages are shown in webbrowser control. I have one button to add html and on click of that I am initializing that webBrowser(HtmlEditor) again. While I am trying to do so sometimes this exception comes:

"TargetInvocation exception" and "Unable to get window handle for WebBrowser Control. Windowless ActiveX control not Supported"

Please Help how to resolve it.