DataMaster is a Protege 3.x plugin. It was not ported to Protege 4.x
Please check out the Cellfie plugin  or the Ontop plugin , one
of which would probably provide you with the functionality that you
Alternatively, if you really need DataMaster, you can use it in
Protege 3.5 (which we no longer support, but you can get it from
) to import your data into an OWL file, and then open that OWL
file in Protege 5.2. There could be some minor issues with the
interpretation of the file, but most probably it would work fine.