First of all, if you enabled the minimization of HTML and CSS files in your settings, before deactivating the plugin deactivates those options.
Then disable the cache, deactivate and delete the plugin, and follow this list to verify that it has been completely uninstalled :
- Delete in your server's .htaccess file everything from # BEGIN WpFastestCache to # END WpFastestCache , both lines included.
- Delete in your server's .htaccess file everything from # BEGIN GzipWpFastestCache to # END GzipWpFastestCache , both lines included.
- Delete in your server's .htaccess file everything from # BEGIN LBCWpFastestCache to # END LBCWpFastestCache , both lines included.
- Delete the folder / wp-content / cache /
- Delete folder / wp-content / plugins / w3-fastest-cache /
Of course, although it seems that, after deactivating it, has deleted the lines of .htaccess deletes the orphaned lines that leaves at the beginning.