XML error cvc-elt

I tried to export one of the issues to xml format. When I tried to validate the xml comparing it with xsd document I got the following :slight_smile:
Cvc-elt.1.a: Cannot Find The Declaration Of Element ‘article’., Line ‘1’, Column '18

Application Version -OJS**

Can anybody help me here? :slight_smile: If needed, I can provide the xml in question.