＆＃39; System.Threading.Tasks.Task（Of Type）＆＃39;无法转换为类型＆＃39;＆＃39;

Question

您好我收到以下错误，我似乎无法重新开始：

  

类型'System.Threading.Tasks.Task的值（Of   Google.Apis.Auth.OAuth2.UserCredential）'无法转换为   'Google.Apis.Auth.OAuth2.UserCredential'。

代码：

Using stream = New FileStream(client_Secrets, FileMode.Open, FileAccess.Read)
    credential = GoogleWebAuthorizationBroker.AuthorizeAsync(GoogleClientSecrets.Load(stream).Secrets, 
                 New YouTubeService.Scope() {YouTubeService.Scope.YoutubeReadonly}, 
                 "user", CancellationToken.None, New FileDataStore(Me.[GetType]().ToString()))
End Using