command zac unr on
French Windows gives the following text:
annuler l''enregistremCette commande annule l''enregistrement d''un
pÃ©riphÃ©rique dans la zone actuelle.
doubling of the single quote, which is common to all the zac
strings that have a single quote - this has been reported as a bug,
It's not possible to determine from this what the correct command for unregistering is, neither the long form nor the short form.