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I;m trying to get WCF Silverlight faults working as per this : MSDN aricle

After adding the SL fault to my Web.config file I get the following warning:

The element 'behavior' has invalid child element 'silverlightFaults'. List of possible elements expected: 'serviceAuthorization, serviceCredentials, serviceMetadata, serviceSecurityAudit, serviceThrottling, dataContractSerializer, serviceDebug, serviceTimeouts, persistenceProvider, workflowRuntime'.

Ignoring the warning doesn't work and my Silverlight application cannot add the WCF service.

Any ideas?

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You should post the relevant part of your web.config, without it all anybody can do is guess what your problem is. –  slugster Jun 7 '10 at 2:43

3 Answers 3

When you add the behavior extension, the type specification must be on a single line. No CRLF allowed in that section.

    <add name="silverlightFaults" type="SilverlightFaultBehavior, Utilities, Version=, Culture=neutral, PublicKeyToken=null" />
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Another potential cause: Make sure your fully qualified name is EXACTLY correct - including whitespace (i.e. you need the spaces after the commas etc).

If you're feeling paranoid, you might want to set a debug point somewhere in your app and pop something like this into the watch window:


and then copy/paste the value.

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Check out http://forums.silverlight.net/forums/p/98385/273886.aspx. Basically, you did not specify the full assembly info in the behavior extension section or your version number is out of synch with the assembly.

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