Issue:
The issue is most likely due to either:
A dead and ghosted Java process; please check via Windows Task Manager, there should be only 1 Java process running.
Or it's due to an OLD Java version.
This should be at least OpenJDK v11 LTS. But better even, to ensure no OLD Java versions are installed, remove them if necessary. Then install the OpenJDK v17 LTS. This is required anyway for the next v71 release.
Use this info here:
After the Java upgrade, please simply restart the fw Server app.