PROBLEM
In some situations, the user is unable to run a custom widget in the ArcGIS Viewer for Flex application.
The issue mainly occurs when the widget is run on a version of ArcGIS Viewer for Flex that is different than the version it was compiled on.
It is highly recommended that users deploy widgets on the same version of ArcGIS Viewer for Flex application.
Note:
For example, if the widget is compiled on ArcGIS Viewer 3.5 for Flex, it may be possible to deploy the widget to ArcGIS Viewer 3.1 for Flex - but this is not supported by Esri.
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