Hi, 

when I tried to publish post at time using "Publish At", uBlogsy throw exception.

2014-11-14 09:00:48,146 [6] ERROR umbraco.presentation.publishingService - [Thread 80] Error publishing node 38881

System.NullReferenceException: Object reference not set to an instance of an object.

   at uDateFoldersy.UmbracoEvents.UmbracoNodeEventsForDateFolders.Flagged(String cachePrefix, String suffix)

   at uDateFoldersy.UmbracoEvents.UmbracoNodeEventsForDateFolders.ContentService_Saved(IContentService sender, SaveEventArgs`1 e)

   at Umbraco.Core.Events.TypedEventHandler`2.Invoke(TSender sender, TEventArgs e)

   at Umbraco.Core.Services.ContentService.SaveAndPublishDo(IContent content, Int32 userId, Boolean raiseEvents)

   at umbraco.cms.businesslogic.web.Document.SaveAndPublishWithResult(User u)

   at umbraco.cms.businesslogic.web.Document.SaveAndPublish(User u)

   at umbraco.presentation.publishingService.CheckPublishing(Object sender)

So, because in background operations,  HttpContext is null => NullReferense exception was thrown. See bellow.

   private bool Flagged(string cachePrefix, string suffix)

   {

      return HttpContext.Current.Items[(object) (cachePrefix + suffix)] is string;

    }

Best regards,

Alexey Badyl | Colours