I recently unboxed a super old CCX400 and noticed that its firmware was REALLY out of date.
The phone could sign in to Teams, but wouldn’t automatically update from the TAC.
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Upon attempting to enable the web interface so that I could log into the phone and manually pull an update from Poly’s servers, I realised the phone had no option to enable the web interface.
A quick Google of the issue and I found this: Unable to enable Web Interface using a Poly CCX 400 using Teams | Poly, formerly Plantronics & Polycom. Poly have documented the steps here to manually download and update the firmware on the handset via USB.
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Once the firmware had been updated, I was then able to enable the web interface, login to the phone and download the update
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