We are trying to allow users to scan documents using Silverlight XAP, which works in a highly trusted browser, from a remote server and we get the following error:
Unhandled error in Silverlight application Failed to create an instance of the object for the specified ProgID.
The failure occurs on the following line:
Dim CommonDialog = AutomationFactory.CreateObject("WIA.CommonDialog")
Application.Current.HasElevatedPermissions and AutomationFactory.IsAvailable both return True.
I can successfully create an instance of unsafe ActiveX controls, for example. Scripting.FileSystemObject:
Dim fso = AutomationFactory.CreateObject("Scripting.FileSystemObject")
Code crashes when working from a production environment on a remote server. When starting from the ASP.NET development server from the local host, the code succeeds, and when called CommonDialog.ShowAcquireImage(), the WIA scan dialog box is displayed.
How can i solve this? (Maybe something specific in the WIA that prevents him from using this method?) What steps can I take to try and debug this?
Update
When I try to open the created Silverlight test page (via the protocol file), I get the same error.
Update 2
Process Monitor shows that AllowLaunchOfElevatedTrustAppsand keys are AllowElevatedTrustAppsInBrowsersuccessfully requested.
Update 3
When protected mode is off, the code works.
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