After switching a domain to use DFS-R rather than FRS for SYSVOL replication you may experience the following error when running dcdiag.exe
Starting test: VerifyReferences Some objects relating to the DC LONDON have problems:  Problem: Missing Expected Value Base Object: CN=LONDON,OU=UK,OU=Domain Controllers,DC=nwtraders,DC=msft Base Object Description: "DC Account Object" Value Object Attribute Name: frsComputerReferenceBL Value Object Description: "SYSVOL FRS Member Object" Recommended Action: See Knowledge Base Article: Q312862 ......................... LONDON failed test VerifyReferences
DFR-S replication of the SYSVOL replication group looks to be otherwise healthy.
This error is caused by some poor logic in dcdiag.exe when the domain controllers have been moved from the default “Domain Controllers” OU. If you move the domain controllers back to the default “Domain Controllers” OU the error will disappear. However, leaving them where they are is likely to cause no problems, other than give you a dcdiag.exe error.
Microsoft plan to fix this in Windows Server 2012.