I’ve been going crazy installing the W3 Total Cache plugin on all my WordPress sites up until a few minutes ago without a hitch. On my 4th site, it returned 3 permission errors which were quickly solved by applying the magical 777 permissions to the folders. The fourth error message that stumped me was “advanced-cache.php is not installed.”
This one is pretty easy to fix. First, download a copy of the W3TC plugin onto your computer. Extract the files to a folder, then upload the file inside the zip file called “advanced-cache.php” to the root of your “wp-content” folder of your site using FTP.
Thanks to A. Fatih Syuhud for the fix.