Preloaded files not on server

Hi,

I use Cache Delivery Method > Simple and Preload enabled. After clicking ‘Preload Cache Now’ it looked like all my files were cached. But I can’t find them anywhere on the server. Where exactly should they be? The 3 folders under /cache/ only have an index.html file in them.

Additionally, the error logs show PHP Warning: Invalid argument supplied for foreach() in /plugins/wp-super-cache/wp-cache.php on line 2050

Thanks!