从maven在nexus中部署工件会出现错误"返回代码是:401"？

我在nexus中部署时遇到401错误.我没有对已安装的nexus进行任何更改.Nexus正在运行localhost:8080/nexus,我可以使用默认用户/密码登录.当我正在运行mvn deploy时,我收到此错误.

这是我的POM.

 testproject
 testproject
 jar
 1.0-SNAPSHOT
 testproject
 http://maven.apache.org
 
  
      releases
      http://localhost:8080/nexus/content/repositories/releases
    
    
       snapshots
       http://localhost:8080/nexus/content/repositories/snapshots
    


 .........

和〜/ .m2/settings.xml

    
        snapshots
        deployment
        deployment123
    
    
        releases
        deployment
        deployment123
    

例外:

Failed to execute goal org.apache.maven.plugins:maven-deploy-plugin:2.7:deploy (default-           deploy) on project testproject: Failed to deploy artifacts: Could not transfer artifact testproject:testproject:jar:1.0-20131213.150615-1 from/to snapshots (http://localhost:8080/nexus/content/repositories/snapshots): Failed to transfer file: http://localhost:8080/nexus/content/repositories/snapshots/testproject/testproject/1.0-SNAPSHOT/testproject-1.0-20131213.150615-1.jar. 
Return code is: 401 -> [Help 1]

请帮我.