===== xml-structure-without-version-tag ===== Starting with PNP 0.6 a version tag was introduced. This message indicated that this tag is missing. After all the xml file seems to be created by a PNP version < 0.6. If this error occurs directly after an update it should be sufficient to wait for the next Nagios check after which the xml file will be newly created. If the error persists the cause may be an old version of ''process_perfdata.pl''. Snippet of the XML structure: ... 4