I've bought a bunch of 560s and some only have self-signed certificates. 8x8 requires the Polycom factory installed certificate for authentication/configuration purposes. They mentioned that I could contact Polycom and pay to have this done, but I can't seem to find anything, or even a number to call or email to contact.
Above depends on the yet currently unknown phone software that your phones are running.
All contact details for Polycom support are within my signature.
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Polycom Global Services
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