751e44c4__Error_Codes___ServiceNow_Wiki__Description
[Error / Data Code] 66 [Error] LDAP_NOT_ALLOWED_ON_NONLEAF [Description] 
Indicates that the requested operation is permitted only on leaf entries. For example, the following types of requests return this error: The client requests a delete operation on a parent entry. The client request a modify DN operation on a parent entry.
LDAP Error Codes - ServiceNow Wiki
Description