as stated within the licensing portal you are not entitled to any updates. Most likely this is due a missing current service contract.
The HDX6000 was sold back in 28/06/2012 via AVICON TECHNOLOGIES
Please contact them for any software upgrade / keys or look into trading in your device to something which is more current.
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
Polycom Global Services
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