title: batch file failed and cannot copy file from one directory to another
body: <p>I created a test.bat program to copy a file from one directory to another. At first it ran well, but after I tested it few times it started to fail to copy! Is there something wrong with my <code>.bat</code> file?</p>
  
  <p>The test.bat is in <code>D:\</code> and the 
    command in test.bat:</p>
  
  <pre><code>copy book_store_log.ldf C:\test
  </code></pre>