title: GTMAppAuth + MailCore: "A stable connection to the server could not be established."
body: <p>under iOS using GMTAuth to access gmail. The test code follows below. The account is accessible with MailCore, essentially similar code, but user/pw no oAuth. Any clues would be appreciated.</p>
  
  <p>I get this log output:</p>
  
  <pre><code>__nw_connection_get_connected_socket_block_invoke 3 Connection has no connected handler
  2017-02-24 17:20:02.977 Example-iOS[38329:24679819] finished checking account.
  2017-02-24 17:20:10.526 Example-iOS[38329:24679819] error loading account: Error Domain=MCOErrorDomain Code=1 "A stable connection to the server could not be established."
  </code></pre>
  
  <p>and this is the code:</p>
  
  <pre><code>self.imapSession = [[MCOIMAPSession alloc] init];
  self.imapSession.hostname = @"imap.google.com";
  self.imapSession.port = 993;
  self.imapSession.username = [_authorization userEmail];
  GTMAppAuthFetcherAuthorization* authorization =
  [GTMAppAuthFetcherAuthorization authorizationFromKeychainForName:kExampleAuthorizerKey];
  self.imapSession.OAuth2Token = authorization.authState.lastTokenResponse.accessToken;
  self.imapSession.authType = MCOAuthTypeXOAuth2;
  self.imapSession.connectionType = MCOConnectionTypeTLS;
  GTMAppAuthExampleViewController * __weak weakSelf = self;
  self.imapSession.connectionLogger = ^(void * connectionID, MCOConnectionLogType type, NSData * data) {
    @synchronized(weakSelf) {
      if (type != MCOConnectionLogTypeSentPrivate) {
        NSLog(@"event logged:%p %li withData: %@", connectionID, (long)type, [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);
        }
      }
    };
  
  // Reset the inbox
  self.messages = nil;
  
  NSLog(@"checking account");
  self.imapCheckOp = [self.imapSession checkAccountOperation];
  [self.imapCheckOp start:^(NSError *error) {
      GTMAppAuthExampleViewController *strongSelf = weakSelf;
      NSLog(@"finished checking account.");
      if (error == nil) {
          // TBD: [strongSelf loadLastNMessages:NUMBER_OF_MESSAGES_TO_LOAD];
      } else {
          NSLog(@"error loading account: %@", error);
      }
      strongSelf.imapCheckOp = nil;
  }];
  }
  </code></pre>