This error occurs when you employ a plugin that Maven could not download. Possible causes for this error are:
- You are referring to a non-existing plugin, e.g. by means of a typo in its group id, artifact id or version.
- You are using a third-party Maven plugin that is not deployed to the central Maven repository and your POM/settings is missing the required
<pluginRepository>
to download the plugin. Note that<repository>
declarations are not considered when looking for the plugin and its dependencies, only<pluginRepositories>
are searched for plugins. - The plugin repository you have configured requires authentication and Maven failed to provide the correct credentials to the server. In this case, make sure your
${user.home}/.m2/settings.xml
contains a<server>
declaration whose<id>
matches the<id>
of the plugin repository to use. See the Maven Settings Reference for more details. - There is a general network problem that prevents Maven from accessing any remote repository, e.g. a missing proxy configuration.
- Maven failed to save the files to your local repository, see LocalRepositoryNotAccessibleException (Copy) for more details.
- The plugin repository you have configured is disabled for the specific version of the plugin you requested. For instance, if you want to use a SNAPSHOT version of a plugin, make sure you don't have
<snapshots><enabled>false</enabled></snapshots>
configured. Likewise, in order to resolve a released version of the plugin, the plugin repository should not be configured with<releases><enabled>false</enabled></releases>
. See the POM Reference for more information on repository configuration.
In those cases, check your POM and/or settings for the proper contents. If you configured the plugin repository in a profile of your settings.xml
, also verify that this profile gets actually activated, e.g. via invoking mvn help:active-profiles
.
In case of a general network-related problem, you could also consult the following articles:
- Configuring a Proxy
- Security and Deployment Settings
- Guide to Remote Repository Access through Authenticated HTTPS
Note: For performance reasons, Maven caches the information that the plugin could not be downloaded. Depending on your setup, you might need to clear this cache by adding the flag -U
to the command line for your corrections to take effect.