title: java.io.FileNotFoundException: can't create a file because of some error in filename , facing this error in only some devices ex:android 4.1.2
body: <pre><code>File external = getExternalFilesDir(null);
  
  //fd is stringbuffer whose value is "year1:semester:2"
  
  File file = new File(external,""+fd.toString()+".txt"); // &lt;----error
  
  FileOutputStream fos = new FileOutputStream(file);
  fos.write(store.getBytes());
  fos.close();
  </code></pre>
  
  <p>This is the exception generated:</p>
  
  <pre><code>W/System.err(29169): java.io.FileNotFoundException: /storage/sdcard0/Android/data/com.example.ddu/files/Year:1Semester:2.txt: open failed: EINVAL (Invalid argument)
  </code></pre>