WCF Service Access to List Items with Managed Metadata Anonymous Access Turned On

Question

I have a WCF service that I deployed to the ISAPI folder which makes calls to not only managed metadata but a list with taxonomy fields.  I need to set values in those fields using the WCF Service because the Client Object Model does not have any way to set these taxonomy values on the list item.  Our SharePoint 2010 portal is also running anonymous access so the user can see some things but not all until they sign in.  I have a Silverlight app that I deploy that makes numerous calls to the WCF service that I deployed to the ISAPI folder.  When I do a trace on the service and run Fiddler I find that the call is not authorized with anonymous access turned on the SharePoint portal.  When I turn anonymous access off it works great.  No problems.  I also created a console app just to test the WCF service for these results and debug the service.  Using CKSDEV I was able to attach the IIS process on the service so that i could fall into the service and see where the authorization access was occurring.  I discovered that with anonymous access turned on it was not even allowing the service to be called.  As if IIS was not allowing it from the SharePoint-80 site.  So then I turned anonymous off and it was able to fall into the service and the current user was shown as the claims identity.  I have tried pretty much everything that has been stated in the forums and blogs.  I have included a web.config and also used the SharePoint factory on the WCF service.  I have also used the claims-based factory with impersonation. 

I am now thinking that this may not be possible to do based on this post:

http://social.technet.microsoft.com/Forums/en-US/sharepoint2010setup/thread/75d087d1-1db2-4063-9936-726012a528a8

If anyone has been able to solve this issue I would greatly appreciate it.  The most common error I get is the "The HTTP request is unauthorized with client authentication scheme 'ntlm'. The authentication header received from the server was 'NTLM'."  This error is with anonymous access turned on. 

Answer 1

Hi Greg,

Thanks for your post!

I am trying to involve some one familiar with this topic to do some further research.

Thanks,
Simon

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Simon Huang

TechNet Community Support

Answer 2

http://sharepointfieldnotes.blogspot.com/2011/08/sharepoint-2010-code-tips-setting.html