Steps: - Enable syspref OAI-PMH and leave OAI-PMH:ConfFile empty. - Set an OAI set on Home › Administration › OAI sets configuration - Remember the setSpec you choose (the real set primary key), for example setSpec==THESIS - Fetch with set=THESIS, you will get records on that set. - Now fetch records with set=bananas. Expected result: A badArgument error like this one: http://digital.bl.fcen.uba.ar/gsdl-282/cgi-bin/oaiserver.cgi?verb=ListRecords&metadataPrefix=oai_dc&set=bananas (Greenstone v2.82) Actual result: List ALL records, like here: http://catalog.bywatersolutions.com/cgi-bin/koha/oai.pl?verb=ListRecords&from=2010-01-01&metadataPrefix=oai_dc&set=bananas Reference: https://www.openarchives.org/OAI/2.0/guidelines-harvester.htm#Sets https://www.openarchives.org/OAI/openarchivesprotocol.html#ErrorConditions