From time to time, you may have to manually clear PrestaShop's cache using your FTP client to restart the machine, for example, if your site only works properly in Debug mode.
To do this it is quite simple, open your favorite FTP client or go through the file manager provided by your host in your hosting management panel.
Go to the installation directory of your PrestaShop store, usually the
Then enter the
In this directory, you should have two subdirectories,
DEV for when the site is in Debug mode and
PROD for the production site where Debug mode is disabled.
You can, without risk, completely erase these two directories,
PROD, and they will reconstitute themselves afterwards.
Version 1.7.3 and lower
On the first versions of the 1.7 branch of PrestaShop these folders are located in the
/app/cache/ directory, but the procedure remains the same and the tip below will apply in the same way, thanks to Jeff from the Friends of Presta association for reminding me this particularity.
When you use your FTP client, it is possible that the large number of files to be deleted takes a long time, but during this time, visitors to your store cause new cache files to be generated.
To avoid this case and to have to put your store in maintenance during the maneuver, you just have to rename these directories
_PROD and to erase these two new directories quietly while your store is fully functional again when the Debug mode is disabled.