The ClientCredentialInfo static method CreateCertificateCredential was called in a context where no client certificate was ...

The ClientCredentialInfo static method CreateCertificateCredential was called in a context where no client certificate was available. 

User Action 
Ensure that only anonymous access is enabled for the ls/auth/sslclient directory and that "Require client certificates" is selected in the Secure Communications dialog box. 

Ensure that CreateCertificateCredential is called only from the authentication Web form in the ls/auth/sslclient directory.