Trouble Uploading Add-ins

Question

I am trying to use some of the 'ready to use add-ins' from the ArcGIS Viewer for Silverlight resources page.  The gallery has several add-ins for download.  I have tried to upload these add-ins in the application builder but have suceeded with only one.  The 'Map scale Settings' Add-in uploaded and is working great. Just what I needed!  However, none of the others will upload.  I specifically need (and tried to upload) the measure tool and the Bookmarks tool. Just for kicks, I tried the print tool also. These will not upload and I get the following error message:

[Arg_NullReferenceException]
Arguments: 
Debugging resource strings are unavailable. Often the key and arguments provide sufficient information to diagnose the problem. See http://go.microsoft.com/fwlink/?linkid=106663&Version=4.1.10329.0&File=mscorlib.dll&Key=Arg_NullReferenceException

I'm not a developer and was not planning on having to code to get these to work. Its probably something simple, but I'm not sure what to investigate. This is a new installation of the SIlverlight Viewer, so it should be complete and up to date.  Anyone else had a problem uploading these add-ins?

Thanks, for any suggestions/direction.

AlexeyTereshenkov · Answer

Good point, Tom. The GP task name is required to be the part of the GP service URL. One can figure out the GP task name from the ArcGIS Services Directory.

TomMagdaleno · Answer

Configuring the print tools is a bit of a trick.  When it prompts you for the url of the print server you need to add some more information to the end of the url.  Mine was 
http://Servername/arcgis/rest/services/Utilities/PrintingTools/GPServer/Export%20Web%20Map%20Task

Be sure to add the part after GPServer or it won't find it.

AlexeyTereshenkov · Answer

Hi Gil,

The Bookmarks and Measure add-ins are already included in the ArcGIS Viewer for Silverlight 3.0 version which is available for download. Consider using this release to take advantage of all the newly introduced functionality.
Just for kicks, I tried the print tool also

ArcGIS Viewer for Silverlight 3.0 supports new ArcGIS 10.1 PrintingTools service for high-quality printing.