SampleApp SimpleViewer Null Exception

Exceptions are thrown when using SimpleViewer for optional elements that are not set within your sample XML Document.

Although the Exceptions are handled within the SimpleViewer, Visual Studio still stops at the point the Exception is Raised.

To work around this issue, you can either press F5 to ignore each exception as is it raised, or you can turn off breaking on User-unhandled 'Common Language Runtime Exceptions' in:
Debug->Windows->Exceptions Settings (Ctrl+Alt+E).

Please see the section Tell the debugger to continue on user-unhandled exceptions in this Microsoft Visual Studio Article for further details.

Note: The code in the SampleApp will have already called FromXmlFile(...) to read in your XML document before the SimpleViewer is launched. If the incoming XML is invalid, an Exception will have been raised by FromXmlFile(...) and displayed in a message box.