title: File not uploading to directory - even when www-data has group permission in the upload folder
body: <p>I have got this to work with 777 file permission: but cannot understand why more restrictive file permissions will not work. </p>
  
  <p><strong>Linux Groups:</strong></p>
  
  <ol>
  <li>alex</li>
  <li>www-data</li>
  </ol>
  
  <p><strong>Linux Users:</strong> </p>
  
  <ol>
  <li>alex (belongs to www-data and alex)</li>
  <li>www-data (belongs to www-data and alex)</li>
  </ol>
  
  <p><strong>Directory Structure</strong> </p>
  
  <p>uploads (directory,owner=alex,group=alex,chmod=660)</p>
  
  <p><strong>Problem</strong></p>
  
  <p>A PHP/Wordpress Admin form (on apache) is used to upload a file to this directory.  If the folder permissions are anything below 777, even 766, the file will not upload, and I cannot understand why.</p>