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If required the PCRaster home directory can be overruled by a global property: PC_RASTER_HOME.
If there is an external installation of pcraster present on the system, it can result in 'No class def found' error. This problem can be fixed by removing the path to the external pcraster installation in the system environment variable PATH.
For Windows the $REGION_HOME$/Modules/pcraster/lib directory should contain the following files:
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