The Ribbon Tab with id: "Ribbon.Read" has not been made available for this page or does not exist. Use Ribbon.MakeTabAvailable(). at Microsoft.Web.CommandUI.Ribbon.Render(HtmlTextWriter writer) at Microsoft.SharePoint.WebControls.SPRibbon.Render(HtmlTextWriter writer)
Add this code in the webpart: Page currentPage = this .Page; SPRibbon ribbon = SPRibbon.GetCurrent( this .Page); SPContext context = SPContext.Current; ribbon.MakeTabAvailable(SPRibbon.ReadTabId); Add the Windows.Web.CommandUI dll reference. Enjoy.