SonarQube Stopping Unexpectedly on Windows

Question

I'm trying to run SonarQube community edition on my local Windows pc. I launch it via the StartSonar.bat command, but it stops prematurely:

C:\dev\sonarqube-7.5\bin\windows-x86-64>StartSonar.bat
wrapper  | --> Wrapper Started as Console
wrapper  | Launching a JVM...
jvm 1    | Wrapper (Version 3.2.3) http://wrapper.tanukisoftware.org
jvm 1    |   Copyright 1999-2006 Tanuki Software, Inc.  All Rights Reserved.
jvm 1    |
jvm 1    | 2019.01.18 23:20:47 INFO  app[][o.s.a.AppFileSystem] Cleaning or creating temp directory C:\dev\sonarqube-7.5\temp
jvm 1    | 2019.01.18 23:20:47 INFO  app[][o.s.a.es.EsSettings] Elasticsearch listening on /127.0.0.1:9001
jvm 1    | 2019.01.18 23:20:47 INFO  app[][o.s.a.p.ProcessLauncherImpl] Launch process[[key='es', ipcIndex=1, logFilenamePrefix=es]] from [C:\dev\sonarqube-7.5\elasticsearch]: C:\Program Files\Java\jdk1.8.0_112\jre\bin\java -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -XX:+AlwaysPreTouch -server -Xss1m -Djava.awt.headless=true -Dfile.encoding=UTF-8 -Djna.nosys=true -Djdk.io.permissionsUseCanonicalPath=true -Dio.netty.noUnsafe=true -Dio.netty.noKeySetOptimization=true -Dio.netty.recycler.maxCapacityPerThread=0 -Dlog4j.shutdownHookEnabled=false -Dlog4j2.disable.jmx=true -Dlog4j.skipJansi=true -Xms512m -Xmx512m -XX:+HeapDumpOnOutOfMemoryError -Delasticsearch -Des.path.home=C:\dev\sonarqube-7.5\elasticsearch -cp lib/* org.elasticsearch.bootstrap.Elasticsearch -Epath.conf=C:\dev\sonarqube-7.5\temp\conf\es
jvm 1    | 2019.01.18 23:20:47 INFO  app[][o.s.a.SchedulerImpl] Waiting for Elasticsearch to be up and running
jvm 1    | 2019.01.18 23:20:48 INFO  app[][o.e.p.PluginsService] no modules loaded
jvm 1    | 2019.01.18 23:20:48 INFO  app[][o.e.p.PluginsService] loaded plugin [org.elasticsearch.transport.Netty4Plugin]
jvm 1    | 2019.01.18 23:20:49 WARN  app[][o.s.a.p.AbstractProcessMonitor] Process exited with exit value [es]: 1
jvm 1    | 2019.01.18 23:20:49 INFO  app[][o.s.a.SchedulerImpl] Process [es] is stopped
jvm 1    | 2019.01.18 23:20:49 INFO  app[][o.s.a.SchedulerImpl] SonarQube is stopped
wrapper  | <-- Wrapper Stopped
C:\dev\sonarqube-7.5\bin\windows-x86-64>

Then I check the es log and it shows the following messages regarding not being able to obtain node locks. What does that mean and how do I resolve it?

2019.01.19 00:17:01 WARN  es[][o.e.b.ElasticsearchUncaughtExceptionHandler] uncaught exception in thread [main]
org.elasticsearch.bootstrap.StartupException: java.lang.IllegalStateException: failed to obtain node locks, tried [[C:\dev\sonarqube-7.5\data\es5\sonarqube]] with lock id [0]; maybe these locations are not writable or multiple nodes were started without increasing [node.max_local_storage_nodes] (was [1])?
    at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:136) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:123) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:70) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:134) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:91) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:84) ~[elasticsearch-5.6.3.jar:5.6.3]
Caused by: java.lang.IllegalStateException: failed to obtain node locks, tried [[C:\dev\sonarqube-7.5\data\es5\sonarqube]] with lock id [0]; maybe these locations are not writable or multiple nodes were started without increasing [node.max_local_storage_nodes] (was [1])?
    at org.elasticsearch.env.NodeEnvironment.<init>(NodeEnvironment.java:261) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.node.Node.<init>(Node.java:265) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.node.Node.<init>(Node.java:245) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.bootstrap.Bootstrap$5.<init>(Bootstrap.java:233) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:233) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:342) ~[elasticsearch-5.6.3.jar:5.6.3]
    at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:132) ~[elasticsearch-5.6.3.jar:5.6.3]
    ... 6 more

One suggestion I found was to run as a non root user. So I tried the approach described in the answer to this question, running StartSonar.bat as "Run without privilege escalation". Unfortunately, that gave me the same result - as did running run as /trustlevel:0x20000 StartSonar.bat.

Update: When I try running StartSonar.bat again today it works fine. The es log suggests maybe "multiple nodes" were started. Not sure about that, since localhost:9000 wasn't showing anything. But maybe there was a "collision" of some kind.