The "PublishedNewsFeedWebPart" Web Part appears to be causing a problem. Object reference not set to an instance of an object.

System.NullReferenceException: Object reference not set to an instance of an object.t Microsoft.SharePoint.Portal.WebControls.PublishedNewsFeedWebPart.RenderWebPart(HtmlTextWriter writer)     at Microsoft.SharePoint.WebPart
Pages.WebPart.Render(HtmlTextWriter writer)     at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)     at Microsoft.SharePoint.WebPartPages.SPChro
me.RenderPartContents(HtmlTextWriter output, WebPart part)