System.FormatException: String was not recognized as a valid DateTime.
   at System.DateTimeParse.Parse(String s, DateTimeFormatInfo dtfi, DateTimeStyles styles)
   at Umbraco.Web.PublishedCache.XmlPublishedCache.PublishedMediaCache.DictionaryPublishedContent.ParseDateTimeValue(String val)
   at Umbraco.Web.PublishedCache.XmlPublishedCache.PublishedMediaCache.DictionaryPublishedContent.<>c__DisplayClass1_0.<.ctor>b__15(String val)
   at Umbraco.Web.PublishedCache.XmlPublishedCache.PublishedMediaCache.DictionaryPublishedContent.ValidateAndSetProperty(IDictionary`2 valueDictionary, Action`1 setProperty, String[] potentialKeys)
   at Umbraco.Web.PublishedCache.XmlPublishedCache.PublishedMediaCache.DictionaryPublishedContent..ctor(IDictionary`2 valueDictionary, Func`2 getParent, Func`3 getChildren, Func`3 getProperty, XPathNavigator nav, Boolean fromExamine)
   at Umbraco.Web.PublishedCache.XmlPublishedCache.PublishedMediaCache.CreateFromCacheValues(CacheValues cacheValues)
   at Umbraco.Web.PublishedCache.XmlPublishedCache.PublishedMediaCache.GetUmbracoMedia(Int32 id)
   at Umbraco.Web.PublishedCache.XmlPublishedCache.PublishedMediaCache.GetById(UmbracoContext umbracoContext, Boolean preview, Int32 nodeId)
   at Umbraco.Web.PublishedCache.ContextualPublishedCache`1.GetById(Boolean preview, Int32 contentId)
   at Umbraco.Web.UmbracoHelper.TypedMedia(Guid id)
   at Umbraco.Web.PropertyEditors.ValueConverters.MediaPickerPropertyConverter.ConvertSourceToObject(PublishedPropertyType propertyType, Object source, Boolean preview)
   at Umbraco.Web.PublishedCache.XmlPublishedCache.XmlPublishedProperty.get_Value()
   at Umbraco.Web.PublishedContentExtensions.GetPropertyValue(IPublishedContent content, String alias)
   at ASP._Page_Views_Partials_Grid_Editors_DocTypeGridEditor_urunGruplari_cshtml.Execute() in c:\inetpub\vhosts\312dizayn.com\httpdocs\Views\Partials\Grid\Editors\DocTypeGridEditor\urunGruplari.cshtml:line 25
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy()
   at System.Web.Mvc.WebViewPage.ExecutePageHierarchy()
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage)
   at System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance)
   at System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer)
   at Umbraco.Core.Profiling.ProfilingView.Render(ViewContext viewContext, TextWriter writer)
   at System.Web.Mvc.HtmlHelper.RenderPartialInternal(String partialViewName, ViewDataDictionary viewData, Object model, TextWriter writer, ViewEngineCollection viewEngineCollection)
   at System.Web.Mvc.Html.PartialExtensions.Partial(HtmlHelper htmlHelper, String partialViewName, Object model, ViewDataDictionary viewData)
   at Our.Umbraco.DocTypeGridEditor.Web.Extensions.HtmlHelperExtensions.RenderDocTypeGridEditorItem(HtmlHelper helper, IPublishedContent content, String editorAlias, String viewPath, String previewViewPath)
   at ASP._Page_app_plugins_doctypegrideditor_render_doctypegrideditor_cshtml.Execute() in c:\inetpub\vhosts\312dizayn.com\httpdocs\App_Plugins\DocTypeGridEditor\Render\DocTypeGridEditor.cshtml:line 28
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy()
   at System.Web.Mvc.WebViewPage.ExecutePageHierarchy()
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage)
   at System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance)
   at System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer)
   at Umbraco.Core.Profiling.ProfilingView.Render(ViewContext viewContext, TextWriter writer)
   at System.Web.Mvc.HtmlHelper.RenderPartialInternal(String partialViewName, ViewDataDictionary viewData, Object model, TextWriter writer, ViewEngineCollection viewEngineCollection)
   at System.Web.Mvc.Html.PartialExtensions.Partial(HtmlHelper htmlHelper, String partialViewName, Object model, ViewDataDictionary viewData)
   at System.Web.Mvc.Html.PartialExtensions.Partial(HtmlHelper htmlHelper, String partialViewName, Object model)
   at ASP._Page_Views_Partials_grid_editors_base_cshtml.Execute() in c:\inetpub\vhosts\312dizayn.com\httpdocs\Views\Partials\Grid\Editors\Base.cshtml:line 20