We have received reply from Silabs.


As macOS High Sierra 10.13 introduces a new feature that requires user approval before loading new third-party kernel extensions, referring to Apple Technical Note TN2459:
https://developer.apple.com/library/con ... index.html
When you download the Mac OSX CP210x VCP driver v5 from silabs website, try to approve the CP210x driver by clicking "Allow" in the Security & Privacy System Preferences panel as TN2459 mentioned and let us know your test result if possible.


Thank you.

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Spirit System developer

Success!! That did it. Everything working well now. Thank you so much.

Thats great!

So it was necessary to allow driver to be loaded as described at the page, right?

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Spirit System developer

Yes. Correct. I had to go to Apple Logo >> System Preferences >> Security & Privacy. Under the Genera tab of "Security and Privacy", I (a) unlocked the "Click the lock to make changes." and (b) chose the "App Store and identified developers" button under "Allow app downloaded from:". While still leaving the "Security and Privacy" window open and the lock unlocked, I re-installed the "Mac OSX CP210x VCP driver v5 from silabs website". The installation process then prompted me to "Allow" installation of these drivers. I never got the "Allow" prompt before I made the changes on "Security & Privacy".

The take home message here is that Apple is has made changes to their security settings, but has not instructed the end-users how to navigate around these changes. Even the AppleCare representative did not help me in this matter and just blamed the app developer.

Very well, thanks a lot!

We will create Step by step guide for the OS X so for new users it will be easier.

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Spirit System developer