The CubePro Duo is a discontinued 3d-systems printer. It uses their standard proprietary cartridges to prevent to use other filaments. In comparison to other printer filaments, their filaments range between 100 and 150$ per spool, which is listed as "1 kg" (though if that is with or without casing is not clear).
From what I could find out about the cartridges, they should contain some kind of identification method to the printer. That it is stuck in Validation means, that it might not be able to read this. So let's try installing the cartridge again, following the handbook p.17!
- Take out the cartridge
- boot the machine
- wait for the machine to ask for filament
- remove the thumbscrew so the filament spool inside the cartridge can turn
- pull out the 30 cm
- cut 5 cm off the end
- insert the material into the Bowden tube of slot 1
- push the material till you get some goop coming out
- mount the cartridge into the slot, make sure it is clamped in tightly.
This should start the validation of the material, at which point you might get told that the colors don't match the print defined colors. Should the cartridge not be validated again but works on the ABS cartridges, the validation method might be broken on this cartridge. Should it not recognize either, the firmware or the detector might be broken.