Hey there.
We had a similar report internally and ultimately the slashes had to be escaped when defining sonar.secretKeyPath.
So in your case:
sonar.secretKeyPath=C:\\Users\\ysong\\Downloads\\sonarqube-developer-9.8.0.63668\\sonar-secret.txt
The default location for the sonar-secret.txt file is
${user.home}/.sonar/sonar-secret.txt
user.home refers to the user directory. As in /Users/myuser or /home/myuser or C:\Users\myuser . Putting sonar-secret.txt in C:\Users\User\.sonar works. If the service is registered and runs as the local system, it should be put in C:\Windows\System32\Config\systemprofile\.sonar
I believe we have a documentation update in the pipe to make this more clear.