Adobe Air Opening/Printing PDF issue

We are seeing this error message occur on some of our clients mac computers when opening/printing pdf's in Adobe Air. We haven't been able to reproduce it in house.

This application requires a version of Adobe AIR which cannot be found.

Please download the latest version of the runtime from

http://www.adobe.com/go/getair,

or contact the application author for an updated version

Our desktop adobe air app crashes at this point.

The following code causes the problem to occur.

var location_Of_PDF_File_String:String = "";

var pdfContainer:HTMLLoader=new HTMLLoader();

pdfContainer.load(new URLRequest(location_Of_PDF_File_String));

popupPDF(pdfContainer);

Everything works fine if the following code is used.

var location_Of_PDF_File_String:String = "";

var request:URLRequest=new URLRequest(location_Of_PDF_File_String);

flash.net.navigateToURL(request);