I have just upgraded from 4.3.8 to 4.7.15 on Drupal 7.50. Everything went well except the
<drupal_root>sites/default/files/civicrm/templates_c directory is rebuilt with the wrong file permissions. The owner should be fclub, not www-data, I think. For example, if I delete this directory in order to solve cached template loading problems and reload the page, it rebuilds itself.
drwxr-sr-x 3 www-data www-data 4096 Jan 11 14:24 templates_c
If I change the owner manually to the correct owner, as all other files and directories, there is an error message about not being able to write to temp files in templates_c.
This seems to be the residual affect of something that is causing multiple problems, including possibly outgoing mail, scheduled jobs and showing the menu.
Edit: Here is what it looks like after upgrading on an exact copy/dev site:
drwxrwsr-x 3 fclub www-data 4096 Jan 8 21:30 templates_c