title: ffmpeg converted .mp4 videos are not playing on windows
body: <p>I am converting videos with extension <code>"flv","avi","mp4","mkv", "mpg", "wmv", "asf", "webm","mov","3gp","3gpp"</code> into <code>"mp4"</code> for a better quality.</p>
  
  <p>Command I am using:</p>
  
  <pre><code>ffmpeg -i &lt;server_path&gt;/g9zyy2qg54qp1l5spo2-mergedFile.webm -strict -2 -vcodec libx264 -preset slow -vb 500k -maxrate 500k -bufsize 1000k -vf 'scale=-1:480 ' -threads 0 -ab 64k -s 640x480 -movflags faststart -metadata:s:v:0 rotate=0 &lt;server_path&gt;/g9zyy2qg54qp1l5spo2-mergedFile7.mp4
  </code></pre>
  
  <p>Videos are working fine everywhere except on Windows. No Video is working on window platform. I tried playing them on firefox, opera, even downloaded them and played on media player software but didn't work at all. </p>
  
  <p>Can you please tell me codecs I should use that make the videos play on windows as well?</p>