I have been impressed by oXygen's XSD schema 'Design' mode, which seamlessly expands the DITA 1.1 topic.xsd definition (contained in a copy of the official DITA xsd directory). However, when I attempt to use oXygen(12.1)'s 'Text' mode contextual schema flattening mechanism, it reports 'failed: unknown protocol: urn'. It appears that the Design mode can handle the 'urn' references, whereas the Text mode cannot. This I find surprising. It maybe that the Design mode has found the 'catalog.xml' file that is provided in the same directory as the 'topic.xsd' file (or it is somehow using oXygen's own catalog files to resolve the definitions using internal resources). Hopefully I have missed something obvious. Any suggestions of a way forward welcome. Best regards, Anthony. PS: I wish to flatten the DITA XSD schemas for later XSLT processing. -- -- ------------------------------------------------------------------------- Michael Anthony Smith, DeltaXML Ltd "Change control for XML" T: +44 1684 891992 E: anthony.smith@deltaxml.com http://www.deltaxml.com Registered in England 02528681 Reg. Office: Monsell House, WR8 0QN, UK