Lync error in Silverlight: Client not trusted

When I try to load my Lync Controls in a Silverlight application I get the error: Client is not trusted. This error doesn't appear when I debug the Silverlight application without the corresponding web project.

This is the code that generates the error:

LyncClient l = LyncClient.GetClient();

This is the error:

AutomationServe开发者_如何学CrException was unhandled by user code
Client is not trusted

What must I do?

This error usually happens because the web site that your Silverlight application is running under isn't in the "Trusted Sites" browser zone. Adding to Trusted Sites should fix it.

Edit: The walkthrough here states:

Security settings for Microsoft Lync 2010 SDK applications require that the host URL for Lync Control Silverlight applications be added to the Trusted sites list in Microsoft Internet Explorer. For information about adding to the Trusted sites list, see Working with Internet Explorer 6 Security Settings.

The probabble cause may be because of the security.Right click the dll and goto properties and set unblock.