Event ID - 635

Event Id635
SourceMicrosoft-Windows-ADFS
DescriptionThe Federation Service encountered an error while loading the trust policy. The specified class was found in the custom module assembly, but the class does not implement the required AD FS interface. Assembly path: %1 Class name: %2 Interface name: %3 If this error occurs during startup of the Federation Service, the Federation Service will be not be able to start, and all requests to the Federation Service will fail until the configuration is corrected. If this error occurs while the Federation Service is running, the Federation Service will continue to use the last trust policy that was loaded successfully. This error may be generated by a non-Microsoft module that is not part of AD FS. User Action Verify that the appropriate assembly and class are configured. Contact the module vendor for further troubleshooting steps.
Event Information According to Microsoft :

Cause :

This event is logged when the Federation Service encountered an error while loading the trust policy.

Resolution :

Implement the required interface: IClaim Transform

Ensure that the appropriate assembly and class are configured. Make sure that the custom transform module DLL file (Transform.dll) has implemented the required interface: IClaim Transform .

The default path of this .dll file is: %windir%:\assembly\GAC\system.web.security.SingleSignOn.claimtransforms\. You can use the Ildasm.exe tool to open the .dll file. The interface IClaim Transform contains a method called TransformClaims(..) , which must be implemented.

Verify :

Verify that you can access the Active Directory Federation Services (AD FS)-enabled application from a client browser and that the resource can be accessed.
Reference LinksEvent ID 635 from Source Microsoft-Windows-ADFS

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