Unfortunately, the pen you bought is for the graphic tablet variant (the kind you plug into your laptop and draw while look up at your laptop screen). It has different frequency from the Tablet PC variants. It won’t work with the Cube Mix Plus, no matter what you do.
For the Cube Mix Plus, it use same kind of digitizer panel as the Samsung Note Series, Thinkpad X220T , Hp 2760p , Fujitsu T902…. so either of their pen would work with the Cube Mix Plus. This full sized Samsung pen is a good choice. It’s affordable, and while not feel as good in hand as the graphic tablet pen but work great.
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