oops, all this time, and all this searching, and it turns out that I forgot about the result values of both CoInitialize(Ex) and CoInitializeSecurity. Apparently CoInitializeSecurity enables you to totally circumvent any stored security settings, but that shouldn't be the point. So best is to guide the system to where the needed stuff is in registry, by applying the AppID you registered the service under. That appears to be the place in registry where DCOMCNFG stores it's data also, which has been re-homed under the Component Services Administrative Tool under Windows 2000 and following.