In order to use PAL queries, either via the PAL language or via the PAL Queries Tab, you must first include the pal-query project as part of your knowledge base. To do this:
{your Protégé-2000 installation directory}/projects/pal-query
folder to the folder
or directory that contains the project in which you want to use PAL
queries. If you want to use the PAL Queries Tab to work with queries in an interactive way, you will need to enable the tab. See Enabling the PAL Constraints and PAL Queries Tabs for more information.
Introduction/Enabling PAL Queries