AzMan COM object in C#, Error calling InitializeClientContextFromStringSid

Using:IAzClientContext ctx = app.InitializeClientContextFromStringSid(user.GetSID(),                    (int)AZROLESLib.tagAZ_PROP_CONSTANTS.AZ_CLIENT_CONTEXT_SKIP_GROUP, null);Where the Entity "user" has a method that returns an SID of the form: "S-1-9-1-1" with S-1-9 being fixed and {0}-{1} being 1 - 1 are the Application GUID and User GUID respectively.I am able to call both:        public void AddSIDToGroup(string Sid, string ApplicationGroup)        {            ...