PS H:\tools\Elasticsearch\6.3.1\bin> .\elasticsearch.exe --debug-env
    -------------
    Elasticsearch
    -------------
    ES_HOME (in order of precedence)
    - HomeDirectoryProcessVariable = H:\Tools\Elasticsearch\6.3.1\
    - HomeDirectoryUserVariable =
    - HomeDirectoryMachineVariable = H:\Tools\Elasticsearch\6.3.1\
    - From executable location = H:\tools\Elasticsearch\6.3.1
    ES_PATH_CONF (in order of precedence)
    - ConfigDirectoryProcessVariable = H:\Tools\Elasticsearch\6.3.1\config
    - ConfigDirectoryUserVariable =
    - ConfigDirectoryMachineVariable = H:\Tools\Elasticsearch\6.3.1\config
    - Fallback to ES_HOME = H:\Tools\Elasticsearch\6.3.1\config

    -------------
    Java
    -------------
    Java paths
    - current = C:\Program Files\Java\jre1.8.0_171\bin\java.exe
    Java Candidates (in order of precedence)
    - JavaHomeProcessVariable =
    - JavaHomeUserVariable =
    - JavaHomeMachineVariable =
    - JdkRegistry64 =
    - JreRegistry64 = C:\Program Files\Java\jre1.8.0_171
    - JdkRegistry32 =
    - JreRegistry32 =
    Java checks
    - Using32BitJava = False
    - JAVA_HOME as machine and user variable = False

I tried it on another VM with a newer Windows10 OS and it works.
Probably just my old Win10 OS not determining the Management iface.

You can probably close the case. This seems to be an anomaly.

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