[Plugin: WP Super Cache] WP Supercache update and delete fail

OK so I was asked by the latest version of my WP blog to update the WP Super Cache. It failed, giving me this:

WP Super Cache Manager
wp-content/advanced-cache.php does not exist or cannot be updated.
Create or update it by executing: cp /homepages/31/d164643851/htdocs/bigdadgib/wp-content/plugins/wp-super-cache/advanced-cache.php /homepages/31/d164643851/htdocs/bigdadgib/wp-content/advanced-cache.php on your server
or by copying /homepages/31/d164643851/htdocs/bigdadgib/wp-content/plugins/wp-super-cache/advanced-cache.php to /homepages/31/d164643851/htdocs/bigdadgib/wp-content/advanced-cache.php some other way.

Cannot continue… fix previous problems and retry.

I tried deactivating, and reactivating. Nothing.

I tried deactivating, deleting the folder and reinstalling the previous version, and not only did I get the same error, but in my Admin/Plugin page it still shows WP Super Cache 0.9.9, instead of the older version I have in place.

Now, when I delete the plugin folder altogether, it still shows up in my plugin page.

Reinstalling and deleting the files from the plugins page results in another error. I am unable to delete the directory from within admin, and even when I deactivate and delete from FTP, it still shows up in my WP-Admin-Plugins page.

This is the main reason I never wanted to use this plugin to begin with. It is too complicated and life is too short.

Can anyone point me to a solution?