3.4.5.6.1 Calling NetrLogonGetTrustRid
If the client requires the RID for the computer account of the calling machine, the caller MUST specify this by passing NULL for both the ServerName and DomainName parameters. Otherwise, a valid ServerName MUST be passed. The client SHOULD be prepared to handle ERROR_ACCESS_DENIED, if the server determines that the client does not have appropriate privileges.