add async keyword to signature of your method. Example:
public async void YourMethod()
{
...
LiveConnectClient liveClient = new LiveConnectClient(this.session);
LiveOperationResult operationResult =
await liveClient.GetAsync("folder.8c8ce076ca27823f.8C8CE076CA27823F!126");
dynamic result = operationResult.Result;
...
}
more info here :http://msdn.microsoft.com/en-us/library/hh191443%28VS.110%29.aspx about return Task or void in section :Return types and parameters