I am using civi 4.7.29 on Wordpress 4.9.4
I noticed that civimail reports is not tracking the email opens after multiple sends. It is just showing "0". In the screen shot, you can see where it is showing click-throughs but not opens.
The checkboxes for tracking opens and click-through are set.
In the email source, I found this URL https://mysite.org/wp-content/plugins/civicrm/civicrm/extern/open.php?q=66
That URL takes me to 404 Error Page.
The permission are:
open.php 755
civicrm/civicrm/extern/ 777
civicrm/civicrm/ 755
civicrm/ 755
Does anything look wrong here? Thank you.