title: Upload xls or xlsx files with codeigniter, mime-type error
body: <p>Well, i believe this is not a Codeigniter problem <em>per se</em> as it is more of a <strong>mime-type</strong>.</p>
  
  <p>I'm trying to upload a file, a xls (or xlsx) file and the mime-type the browser and the php report is <strong>application/octet-stream</strong> instead of <strong>application/excel</strong>, <strong>application/vnd.ms-excel</strong> or <strong>application/msexcel</strong> for a xls file. Of course codeigniter upload plugin will report an error (invalid file type) as it tries to match the file extension with the mime-type.</p>
  
  <p>The weird(est) thing might be that the same code worked for months and now stopped working with the latest Chrome (16.0.912.77), Firefox (10.0) and IE9. </p>
  
  <p>Has anyone had the same (or similar) problem and care to share the solution? </p>
  
  <p>Thank you very much.
  PS: I won't provide code as it's not really a code matter, but if necessary i'll upload some snippets.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>It might be relevant: the error doesn't happen with same browsers on a similar configuration, but with MS Office instead of Libre Office (on my pc). It doesn't happen on a GNU/Linux based + Libre Office system either. SO, could it be Windows playin' hard on the open source suite, or the Libre Office changing the mime-types just for the heck of it?</p>