Event ID 633 — Trust Policy and Configuration

Applies To: Windows Server 2008 R2

The Active Directory Federation Services (AD FS) trust policy file defines the set of parameters that a Federation Service requires to identify partners, certificates, account stores, claims, and the various properties of these entities that are associated with the Federation Service.

Event Details

Product: Windows Operating System
ID: 633
Source: Microsoft-Windows-ADFS
Version: 6.1
Symbolic Name: CustomModuleExceptionInstantiating
Message: The Federation Service encountered an error while loading the trust policy. An exception was thrown during instantiation of a custom module class from a custom module assembly.
Assembly path: %1
Class name: %2

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.

Additional Data
Exception information:


Configure the appropriate assembly and class

Make sure that the appropriate assembly and class are configured. When you point to a custom transform module dynamic-link library (DLL) file, make sure that the Class name that is specified on this tab exists in that DLL file.

To perform this procedure, you must be a member of the local Administrators group, or you must have been delegated the appropriate authority.

To specify the file path for the transform module settings in the trust policy:

  1. On the federation server, click Start, point to Administrative Tools, and then click Active Directory Federation Services.
  2. In the console tree, under Federation Service, right-click Trust Policy, and then click Properties.
  3. Click the Transform Module tab, and then type the file path in DLL file.

For further troubleshooting, contact the module vendor.


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.

Trust Policy and Configuration

Active Directory Federation Services