I tried to install MySQL database plugin and selected the checkbox to restart after installing. It then stopped the Jenkins windows service and removed it.

I then tried to run Jenkins with java -jar jenkins.war, and it started as if it was a fresh install.

On my EventViewer I can see 2 warnings at that time:

SIGINT to 9800 failed - Killing as fallback

SIGINT to 7460 failed - Killing as fallback

Service stopped successfully

Very weird.

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