Could not calculate build plan: Plugin org.apache.maven.plugins:maven-jar-plugin:2.3.2 or one of its dependencies could not be resolved

Try cleaning the local .m2/repository/ folder manually using rm -rf and then re build the project. Worked for me after trying every possible other alternative(reinstalling eclipse, pointing to the correct maven version in eclipse, proxy settings etc)

I was able to solve the same problem with different solution.

The solution that worked for me was to Right click project "pom.xml" in eclipse and select "Maven Install".

I solved it now. However it only is solved in Netbeans. Not sure why eclipse still won't take the settings.xml that is changed. The solution is however to remove/comment the User/Password param in settings.xml

Before:

<proxies>
    <proxy>
      <id>optional</id>
      <active>true</active>
      <protocol>http</protocol>
      <username>proxyuser</username>
      <password>proxypass</password>
      <host>proxyserver.company.com</host>
      <port>8080</port>
      <nonProxyHosts>local.net|some.host.com</nonProxyHosts>
    </proxy>
  </proxies> 

After:

<proxies>
    <proxy>
      <id>optional</id>
      <active>true</active>
      <protocol>http</protocol>
      <host>proxyserver.company.com</host>
      <port>8080</port>
      <nonProxyHosts>local.net|some.host.com</nonProxyHosts>
    </proxy>
  </proxies>