Cannot set Preferred Global Catalog (AF) and Configuration Domain Controller (AF) to values that belong to two different ...

Cannot set Preferred Global Catalog (AF) and Configuration Domain Controller (AF) to values that belong to two different Account Forests: {0} and {1}. You can use PreferredAFServer parameter to set both properties to the same value, or AFConfigurationDomainController and PreferredAFGlobalCatalog in single cmdlet invocation to set these properties to different values or null.