I think something is wrong with the new Mac installer. Have tried a few times now on different machines. It deletes v3.81 which is the previously installed version but does not replace it. Are others having the same problem?
I only got around and tried this today on my MacBook Air running High Sierra.
It uninstalled the 3.7.0 version and then installed the 3.9 Version without issues.
If you still have this issue please work with your Polycom reseller to get this into support.
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
Polycom Global Services
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