Published: Guidance For SharePoint 2010 Architects and Developers
December 4, 2010
Windows Phone 7 Application Screenshots
December 29, 2010

Recently I was creating a Sandboxed Compatible Visual Web Part  to display an AJAX Bing Maps control.  When I added the Web Part to the page for first time to test it I received the following error.

Unhandled exception was thrown by the sandboxed code wrapper’s Execute method in the partial trust app domain: The UserCodeToken is invalid.

I was surprised when I saw no one had posted a solution to this issue on the Internet.  To make the error go away I simply reset the SharePoint 2010 User Code Host Service.