I just found a helpful tip on how to fix the broken automatic update feature in WordPress.

All that was actually missing was a line in the main .htaccess file! I just added:

AddType x-mapp-php5 .php

to my .htaccess file (inside the # BEGIN WordPress -  # END WordPress markers) and – voila it works!

I wish I had something as fancy as that for ZenMagick…

DISCLAIMER: I can’t guarantee that this works for everyon; aparently there are more issues which lead to the reactivation of the WordPress Automatic Upgrade plugin, so you’ll have to try for yourself. Good luck!