Webform results don't download We've been using our Drupal webforms for years. Suddenly today, if an authorized user or the admin tries to download the results, the resulting file is 0bytes. The data is definitely there. I am unsure how to even troubleshoot this problem.

The really odd thing is that my dev site is a near identical copy of the live site and it works on the dev site (but the results are outdated). Whatever changed on the live site would have been in the last couple weeks and I can't think of what may have caused it that I wouldn't have implemented on the dev site first.

Drupal 7.50 Commons, webform 7.x-1.0. Let me know what other information would be helpful to provide, thanks!

Things I've Tried, to no avail:


downloaded the results into different formats
downloaded results as regular staff and admin user
downloaded only final and non-draft results
I checked the permissions of the temporary files for our theme and sure enough, they were wrong. I am not sure what caused them to change, but they were set to root, whereas the dev site was set for www-data for both user and group. On our Debian server, Drupal uses the temporary files located at /tmp/example_theme. 

To fix:

sudo chown -R www-data /var/example_theme

sudo chgrp -R www-data /var/example_theme

That fixed this and many other problems we were having today.