when i 'mvn clean' I get The plugin 'org.apache.maven.plugins:maven-clean-plugin' does not exist or no valid version could be found
Also, when I 'mvn -U', I get [INFO] artifact org.apache.maven.plugins:maven-site-plugin: checking for updates from central [WARNING] *** CHECKSUM FAILED - Error retrieving checksum file for org/apache/maven/plugins/maven-site-plugin/maven-metadata.xml - IGNORING I tried adding a proxy repository for http://people.apache.org/maven-snapshot-repository/, and directing it to Archiva's 'internal', which I have configured as a mirrorOf *. What should I have?
