DCDIAG - LDAP Error 0x5e (94) - VerifyEnterpriseReferences

Hello,

We are preparing to run ADPREP against our Windows Server 2008 R2 domain in preparation to allow Windows Server 2012 R2 domain controllers.

In the process, I discovered this from our DCDIAG output. Can anyone assist as to what this issue might be and best recommendations to resolve?

Starting test: VerifyEnterpriseReferences         LDAP Error 0x5e (94) - No result present in message. 
         ......................... CTL-BDC3 failed test         VerifyEnterpriseReferences

Thanks!

JTW