The AD FS Web Agent Authentication Service was not able to start. The authentication service has not been configured to run ...

Windows 7

The AD FS Web Agent Authentication Service was not able to start. The authentication service has not been configured to run as a principal that has been granted the "Act as part of the operating system" privilege (SeTcbPrivilege). 

Users will not be able to access protected resources until the authentication service can be restarted. 

User Action 
Either grant the AD FS authentication service principal the "Act as part of the operating system" privilege or configure the service to run as a principal that has already been granted the "Act as part of the operating system" privilege. (For example, configure the authentication service to run as LocalSystem.)

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