Event ID - 634

Event Id634
SourceMicrosoft-Windows-ADFS
DescriptionThe Federation Service encountered an error while loading the trust policy. The specified class could not be instantiated from the 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.
Event Information According to Microsoft :

Cause :

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

Resolution :

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 review the file path that is specified in DLL file .
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 634 from Source Microsoft-Windows-ADFS

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