BToE 3.4.2 for Windows 10 has been released => here <=
This is a Windows 10 release only. Any other issues with any other Windows Version need to be reported to Polycom via the official channel.
Happy to report that this release fixes the Win10 install problem and now connects fine with secure boot enabled.
This might be Windows issue as well as outdated driver version. Each scenario is solvable by turning of digital signature enforcement for current Windows session. Here's an explanation for each Windows version http://freewisdoms.com/windows-cannot-verify-the-digital-signature-code-52-driver-fix/
Be aware that this solution is active only for current Windows session, which means it will be turned off after the restart. Luckily, the procedure can be redone as many times as you need. Good luck.
as this is an old post discussing no longer supported software versions and as we have fixed this I close this to prevent further replies.