Please try this and see what happens:
chmod -R 755 /var/www/html/fog
and then see what happens.
Still doing the same thing
I have the same problem, snapins will never be added to the snapintasks or snapinjobs tables when creating a single or all snapins task. They will be added and run normally if created as part of a download task however. I’m running a single Centos 7 server and am on 4501.