Therion error (cannot find proj.db): no usable coordinate transformation found

therion 6.3.3 (2025-01-06)
cavern - Survex 1.4.15
initialization file: C:\Program Files\Therion/therion.ini
reading ... done
configuration file: P:\geospeo\speosilex\ps\ps_cerna\Cerna_20231201\model3d\cerna.thconfig
reading ... done
reading source files ... proj_create_operation_factory_context: Cannot find proj.db
proj_create: Cannot find proj.db
proj_create: no database context specified
proj_create: Cannot find proj.db
proj_create: no database context specified
proj_create_operations: missing required input

C:\Program Files\Therion\therion.exe: error -- no usable coordinate transformation found