I have this in my error log
[Fri Feb 03 17:35:00 2017] [error] [client 192.168.175.24] PHP Warning: htmlspecialchars(): charset `UTF=8’ not supported, assuming utf-8 in public_html/plugins/importexport/crossref/filter/IssueCrossrefXmlFilter.inc.php on line 113, referer: /management/importexport/plugin/CrossRefExportPlugin
[Fri Feb 03 17:35:01 2017] [error] [client 192.168.175.24] PHP Warning: DOMDocument::schemaValidate(): Invalid Schema in /public_html/lib/pkp/classes/xslt/XMLTypeDescription.inc.php on line 126, referer: /management/importexport/plugin/CrossRefExportPlugin
[Fri Feb 03 17:35:01 2017] [error] [client 192.168.175.24] ojs2: Valittuja kohteita ei voitu muuntaa., referer: management/importexport/plugin/CrossRefExportPlugin