Having read the existing posts with similar problem and tried the steps and suggestions give, the problem still exists.
The Wwise Launcher version is 2020.3.1.717, installed Unity version 2018.4.0f1, 2019.4.8f1, Wwise version 2019.2.5 and Windows 10 pro, version 2004.
A message occurred when trying to integrate Wwise into a Unity project created using 2019.4.8f1, showing "Failed to get Unity version. Please validate the Unity Installation field.". The message still occurs even after choosing Unity.exe path manually.
The problem occurs on revious projects that already integrated with Wwise, and all the 'Open in Unity' bottons are greyed out.
Any ideas to resolve this? Thanks alot!