尝试登录但无法登录。我的tomcat-users.xml，按照我在这里看到的进行了修改。

    <?xml version="1.0" encoding="UTF-8"?>
   <tomcat-users>
      <role rolename="manager-gui"/>
      <role rolename="manager-script"/>
      <role rolename="manager-jmx"/>
      <role rolename="manager-status"/>
      <role rolename="admin-gui"/>
      <role rolename="admin-script"/>
      <user username="admin" password="admin" roles="manager-gui, manager-script, manager-jmx, manager-status, admin-gui, admin-script"/>
    </tomcat-users>

有什么建议么？