WP SC not working after updating to 1.5.7.1

Hello,

My configuration: WP 4.8.2 in French with PHP 5.6.30, MySQL 5.5.55-0+deb7u1-log – Linux
My site URL: https://www.linuxrouen.fr/wp/

I’m using WP Super Cache 1.5.7.1 which I updated less than one week ago with a final message saying that the update process went well.
Before updating WP Super Cache, it was working well.

But since, when trying to access it I’m getting the following error message:
“Erreur: Your cache directory () did not exist and couldn’t be created by the web server. Check permissions. Impossible de continuer… Résolvez les problèmes susmentionnés et réessayez.”
I haven’t modified any permissions and my other plug-ins are still working well.

So, going to the WP Installed Extensions to list them, I have under WPSC the following message:
“WP Super Cache doit être configuré. Allez sur La page d’administration pour activer et configurer le plugin.”
i.e. “WPSC must be configured. Go to the Admin page for activating and configuring the plugin!”
But in the same time WPSC is indicated as being Activated just under WP Super Cache !

Clicking on the “Admin page” link in the above message, I’m always getting my original error message!
Clicking on the “Options” link just under WP Super Cache, I’m always getting my original error message!

Now, when Clicking on the “Désactiver” (Deactivate) link just under WP Super Cache, I’m getting under WP Super Cache two links: Activate and Delete.
Clicking on Activate, I’m getting back to the problem-error mentioned above.

Any idea about what I can do for fixing this bloody problem?
Thanks.

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