An error occurred while attaching module (Dynamicweb.Frontend.Content)

System.Xml.XmlException: There are multiple root elements. Line 1, position 43.
   at System.Xml.XmlTextReaderImpl.Throw(Exception e)
   at System.Xml.XmlTextReaderImpl.Throw(String res, String arg)
   at System.Xml.XmlTextReaderImpl.ParseDocumentContent()
   at System.Xml.XmlTextReaderImpl.Read()
   at System.Xml.XmlLoader.LoadDocSequence(XmlDocument parentDoc)
   at System.Xml.XmlLoader.Load(XmlDocument doc, XmlReader reader, Boolean preserveWhitespace)
   at System.Xml.XmlDocument.Load(XmlReader reader)
   at System.Xml.XmlDocument.LoadXml(String xml)
   at Dynamicweb.Modules.Properties.LoadProperty(String xml, Boolean merge)
   at Dynamicweb.Modules.ContentModule.InitializeModule(Paragraph renderingParagraph, PageView pageviewContext)
   at Dynamicweb.Ecommerce.Frontend.Frontend.InitializeModule(Paragraph renderingParagraph, PageView pageviewContext)
   at Dynamicweb.Frontend.Content.GetModuleOutput(Paragraph paragraph, PageView pageview)