title: Maven doesn't download dependencies: "The repository system is offline"
body: <p>I'm not comfortable with Maven, but I managed to make it work for a while with Netbeans. But suddenly, Maven refuses to download new dependencies :</p>
  
  <pre><code>org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal on project matheos: Could not resolve dependencies for project lecoleopensource:matheos:jar:1.4.4-SNAPSHOT: The repository system is offline but the artifact org.docx4j:docx4j-ImportXHTML:jar:3.2.2 is not available in the local repository.
      at org.apache.maven.lifecycle.internal.LifecycleDependencyResolver.getDependencies(LifecycleDependencyResolver.java:210)
      at org.apache.maven.lifecycle.internal.LifecycleDependencyResolver.resolveProjectDependencies(LifecycleDependencyResolver.java:117)
      at org.apache.maven.lifecycle.internal.MojoExecutor.ensureDependenciesAreResolved(MojoExecutor.java:258)
      at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:201)
      at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
      at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
      at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:84)
      at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
      at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
      at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
      at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320)
      at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
      at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
      at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
      at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:606)
      at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290)
      at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230)
      at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
      at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352)
  Caused by: org.apache.maven.project.DependencyResolutionException: Could not resolve dependencies for project lecoleopensource:matheos:jar:1.4.4-SNAPSHOT: The repository system is offline but the artifact org.docx4j:docx4j-ImportXHTML:jar:3.2.2 is not available in the local repository.
      at org.apache.maven.project.DefaultProjectDependenciesResolver.resolve(DefaultProjectDependenciesResolver.java:189)
      at org.apache.maven.lifecycle.internal.LifecycleDependencyResolver.getDependencies(LifecycleDependencyResolver.java:185)
      ... 22 more
  Caused by: org.sonatype.aether.resolution.DependencyResolutionException: The repository system is offline but the artifact org.docx4j:docx4j-ImportXHTML:jar:3.2.2 is not available in the local repository.
      at org.sonatype.aether.impl.internal.DefaultRepositorySystem.resolveDependencies(DefaultRepositorySystem.java:375)
      at org.apache.maven.project.DefaultProjectDependenciesResolver.resolve(DefaultProjectDependenciesResolver.java:183)
      ... 23 more
  Caused by: org.sonatype.aether.resolution.ArtifactResolutionException: The repository system is offline but the artifact org.docx4j:docx4j-ImportXHTML:jar:3.2.2 is not available in the local repository.
      at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:538)
      at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolveArtifacts(DefaultArtifactResolver.java:216)
      at org.sonatype.aether.impl.internal.DefaultRepositorySystem.resolveDependencies(DefaultRepositorySystem.java:358)
      ... 24 more
  Caused by: org.sonatype.aether.transfer.ArtifactNotFoundException: The repository system is offline but the artifact org.docx4j:docx4j-ImportXHTML:jar:3.2.2 is not available in the local repository.
      at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:348)
      ... 26 more
  </code></pre>
  
  <p>Something is apparently offline, but I don't understand why and how to fix this.</p>
  
  <p>Here is a part of my pom file :</p>
  
  <pre><code>    &lt;dependencies&gt;
          &lt;!-- docx4j : converts html to docx --&gt;
          &lt;dependency&gt;
                  &lt;groupId&gt;org.docx4j&lt;/groupId&gt;
                  &lt;artifactId&gt;docx4j&lt;/artifactId&gt;
                  &lt;version&gt;3.2.2&lt;/version&gt;
          &lt;/dependency&gt;
  
          &lt;!-- pdf2dom : converts pdf to html --&gt;
          &lt;!--dependency&gt;
                  &lt;groupId&gt;net.sf.cssbox&lt;/groupId&gt;
                  &lt;artifactId&gt;pdf2dom&lt;/artifactId&gt;
                  &lt;version&gt;1.3&lt;/version&gt;
          &lt;/dependency--&gt;
  
  
      &lt;/dependencies&gt;
  </code></pre>
  
  <p>What I don't understand is that it used to work fine until now...</p>
  
  <p>I don't understand Maven very well, so tell me if I should have given other details. Thank you !</p>
  
  <p><strong>EDIT :</strong> I removed the repository section, still the same. I edited the artefactID to docx4j, still the same.</p>