If you are trying to copy markup and its associated attributes from one file to another that has different tags sets, Arbortext Editor will convert as many of the undeclared tags into declared tags as possible. Any tags that are not converted will be recognized as invalid markup appear in red with a strikethrough. Any attributes which are legal in the new document upon the conversion will become real attributes in the new document. Any attributes that are not converted will remain in the document and be identified as invalid markup and you must manually convert them.