maven 3.6.2 mvn帮助：系统报告错误

下面是错误日志，我没有使用网络代理。我已经设置了镜像和存储库，所以我很困惑它到底出了什么问题。我可以在浏览器中打开镜像站点，因此我认为我的网络是正常的

    Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/codehaus/mojo/maven-metadata.xml
    Downloading from nexus-aliyun: http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-metadata.xml
    [WARNING] Could not transfer metadata org.apache.maven.plugins/maven-metadata.xml from/to nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public): Transfer failed for http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-metadata.xml
    [WARNING] Could not transfer metadata org.codehaus.mojo/maven-metadata.xml from/to nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public): Transfer failed for http://maven.aliyun.com/nexus/content/groups/public/org/codehaus/mojo/maven-metadata.xml
    [WARNING] Failure to transfer org.apache.maven.plugins/maven-metadata.xml from http://maven.aliyun.com/nexus/content/groups/public was cached in the local repository, resolution will not be reattempted until the update interval of nexus-aliyun has elapsed or updates are forced. Original error: Could not transfer metadata org.apache.maven.plugins/maven-metadata.xml from/to nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public): Transfer failed for http://maven.aliyun.com/nexus/content/groups/public/org/apache/maven/plugins/maven-metadata.xml
    [WARNING] Failure to transfer org.codehaus.mojo/maven-metadata.xml from http://maven.aliyun.com/nexus/content/groups/public was cached in the local repository, resolution will not be reattempted until the update interval of nexus-aliyun has elapsed or updates are forced. Original error: Could not transfer metadata org.codehaus.mojo/maven-metadata.xml from/to nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public): Transfer failed for http://maven.aliyun.com/nexus/content/groups/public/org/codehaus/mojo/maven-metadata.xml
    [INFO] ------------------------------------------------------------------------
    [INFO] BUILD FAILURE
    [INFO] ------------------------------------------------------------------------
    [INFO] Total time:  2.745 s
    [INFO] Finished at: 2020-03-12T14:26:55+08:00
    [INFO] ------------------------------------------------------------------------
    [ERROR] No plugin found for prefix 'help' in the current project and in the plugin groups [org.apache.maven.plugins, org.codehaus.mojo] available from the repositories [local (E:\apache-maven-3.6.3\repository), nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public)] -> [Help 1]
    org.apache.maven.plugin.prefix.NoPluginFoundForPrefixException: No plugin found for prefix 'help' in the current project and in the plugin groups [org.apache.maven.plugins, org.codehaus.mojo] available from the repositories [local (E:\apache-maven-3.6.3\repository), nexus-aliyun (http://maven.aliyun.com/nexus/content/groups/public)]
        at org.apache.maven.plugin.prefix.internal.DefaultPluginPrefixResolver.resolve (DefaultPluginPrefixResolver.java:95)
        at org.apache.maven.lifecycle.internal.MojoDescriptorCreator.findPluginForPrefix (MojoDescriptorCreator.java:266)
        at org.apache.maven.lifecycle.internal.MojoDescriptorCreator.getMojoDescriptor (MojoDescriptorCreator.java:220)
        at org.apache.maven.lifecycle.internal.DefaultLifecycleTaskSegmentCalculator.calculateTaskSegments (DefaultLifecycleTaskSegmentCalculator.java:104)
        at org.apache.maven.lifecycle.internal.DefaultLifecycleTaskSegmentCalculator.calculateTaskSegments (DefaultLifecycleTaskSegmentCalculator.java:83)
        at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:89)
        at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:305)
        at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:192)
        at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:105)
        at org.apache.maven.cli.MavenCli.execute (MavenCli.java:957)
        at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:289)
        at org.apache.maven.cli.MavenCli.main (MavenCli.java:193)
        at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
        at jdk.internal.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:62)
        at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke (Method.java:567)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:282)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:225)
        at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:406)
        at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:347)
        [ERROR] Re-run Maven using the -X switch to enable full debug logging.
        [ERROR]
        [ERROR] For more information about the errors and possible solutions, please read the following articles:
        [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/NoPluginFoundForPrefixException

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我的操作系统是windows 10。看起来像是网络错误…我的操作系统是windows 10。看起来像是网络错误。。。