public async void ExecuteAddAclCommand(object parameter) { Busy = true; BusyContent = "Adding ACL"; try { var identity = new IdentityDescriptionObject(SelectedIdentity.Mrn, SelectedIdentity.Name); await Task.Factory.StartNew(() => { var visService = new VisService(); visService.AuthorizeIdentities(Id, new List <IdentityDescriptionObject> { identity }); }); AclList.Add(identity); } catch (Exception ex) { MessageBox.Show(ex.ToString()); } finally { Busy = false; } }