Insufficient Permission [403] on PlusDomainsService activity insert

Getting an exeption on activity insert method {"Google.Apis.Requests.RequestError\r\nInsufficient Permission [403]\r\nErrors [\r\n\tMessage[Insufficient Permission] Location[ - ] Reason[insufficientPermissions] Domain[global]\r\n]\r\n"} The original code is:

UserCredential credential;
           using (var stream = new FileStream("client_secrets.json", FileMode.Open, FileAccess.Read))
            {
                credential = await GoogleWebAuthorizationBroker.AuthorizeAsync(
                     GoogleClientSecrets.Load(stream).Secrets,
                     new[] { PlusDomainsService.Scope.PlusMe, PlusDomainsService.Scope.PlusLogin, PlusDomainsService.Scope.PlusStreamWrite },
                     _settings.ChannelName,
                     CancellationToken.None
                      );
            }
            var googlePlusService = new PlusDomainsService(new BaseClientService.Initializer()
            {
                HttpClientInitializer = credential,
                ApplicationName = "Application Name"
            });
            PlusDomainsAclentryResource resource = new PlusDomainsAclentryResource();
            resource.Type = "public";
            List<PlusDomainsAclentryResource> aclEntries = new List<PlusDomainsAclentryResource>();
            aclEntries.Add(resource);
            Acl acl = new Acl();
            acl.Items = aclEntries;
            acl.DomainRestricted = true;
            var activityData = new Activity.ObjectData() { OriginalContent = "Hello world"};
            Activity activity = new Activity()
            {
                Access = acl,
                Object__ = activityData
            };
            var insertRequest = googlePlusService.Activities.Insert(activity, "me");
            var result = await insertRequest.ExecuteAsync();

client_secrets.json is a downloaded file from https://console.developers.google.com/apis/credentials OAuth 2.0

UPD: replaced _credential with credential, becouse of typo

[ansydor]

The issue was a misunderstand between Google+ domain and Google+

[LindaLawton]

Its not the application that needs access to Google+ domain its the user you are logging in with. If that user does not have access to write to your Google+ domains account then you are going to get the error message.

Insufficient Permission

The user does not have permissions not the application. Trying increasing that users permissions on the domain or login with a user that does have access already.