title: npm ERR! arg Argument starts with non-ascii dash, this is probably invalid: [ '- g', 'appium' ]
body: <p>when i try to Installing Appium 
  Open Command Prompt/Terminal and type the following command to install Appium:</p>
  
  <p><strong>npm install –g appium</strong></p>
  
  <p><strong>showing</strong></p>
  
  <p>npm ERR! arg Argument starts with non-ascii dash, this is probably invalid: [ '-
  g', 'appium' ]
  npm ERR! code EINVALIDTAGNAME
  npm ERR! Invalid tag name "-g": Tags may not have any characters that encodeURIC
  omponent encodes.</p>
  
  <p>npm ERR! A complete log of this run can be found in:
  npm ERR!     C:\Users\vipin\AppData\Roaming\npm-cache_logs\2018-08-23T07_34_08_
  495Z-debug.log</p>
  
  <p>NB:- Node.js v8.11.4 and npm 5.6.0</p>