Seems a bit more, they are 2.10.0.xxxx whereas now we are on 2.10.1.xxxx
Try upgrading one phone manually to 2.10.1.6806 from the manufacturer's site
As soon as it is done then try again from your 3CX management console.
Are you using 3CX V16?
The problem is that it appears to be trying to download from the sbc and not the 3cx server. It continues to fail
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