Preloading does not work properly

I use your plugin in a multisite network. The preloading does not work properly. If I click on the button to pre load now, nothing happens. I disabled the normal cronjob and added one in my Ubuntu settings. But for test purposes, I simply called the cronjob file itself. Every time when I do this, both emails (initial-email and finish-email) comes together and nothing happens. I have to click on the pre load button to clear it. Then I need to click again to start the pre load. Sometimes it works then, if I call the cronjob file again. Sometimes nothing happens. Any idea how this can be fixed? Here is the log:

```
14:54:57 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload Not serving wp-admin requests.
14:54:57 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:54:57 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:54:57 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload In WP Cache Phase 2
14:54:57 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload Setting up WordPress actions
14:54:57 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload Not caching wp-admin requests.
14:55:00 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:55:00 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:55:00 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload In WP Cache Phase 2
14:55:00 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload Setting up WordPress actions
14:55:00 7686 /wp-admin/options-general.php?page=wpsupercache&tab=preload Not caching wp-admin requests.
14:55:05 7693 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:55:05 7693 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:55:05 7693 /wp-admin/admin-ajax.php In WP Cache Phase 2
14:55:05 7693 /wp-admin/admin-ajax.php Setting up WordPress actions
14:55:05 7693 /wp-admin/admin-ajax.php Not caching wp-admin requests.
14:55:19 7698 /wp-cron.php Removing auth from $_COOKIE to allow caching for logged in user (wordpress_logged_in_someClibberishCodeFragments123456789)
14:55:19 7698 /wp-cron.php wp_cache_get_cookies_values: return:
14:55:19 7698 /wp-cron.php wp_cache_get_cookies_values: return:
14:55:19 7698 /wp-cron.php In WP Cache Phase 2
14:55:19 7698 /wp-cron.php Setting up WordPress actions
14:55:19 7698 /wp-cron.php Created output buffer
14:55:19 7698 /wp-cron.php wp_cache_get_cookies_values: return:
14:55:19 7698 /wp-cron.php supercache dir: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:55:19 7698 /wp-cron.php wpcache_do_rebuild: doing rebuild for /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:55:19 7698 /wp-cron.php wpcache_do_rebuild: exiting as directory is not a directory: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:55:19 7698 /wp-cron.php maybe_stop_gc: GC flag not found. GC will go ahead..
14:55:19 7698 /wp-cron.php wp_cache_gc_cron: Set GC Flag. (/the-path-to/wp-content/cache/my-domain.com_wp_cache_gc.txt)
14:55:19 7698 /wp-cron.php Cache garbage collection.
14:55:19 7698 /wp-cron.php Cleaning expired cache files in /the-path-to/wp-content/cache/blogs/blog/
14:55:19 7698 /wp-cron.php GC completed. GC flag deleted.
14:55:19 7698 /wp-cron.php scheduled wp_cache_gc for 10 seconds time.
14:55:20 7701 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:55:20 7701 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:55:20 7701 /wp-admin/admin-ajax.php In WP Cache Phase 2
14:55:20 7701 /wp-admin/admin-ajax.php Setting up WordPress actions
14:55:20 7701 /wp-admin/admin-ajax.php Not caching wp-admin requests.
14:55:28 7698 /wp-cron.php wp_cron_preload_cache: doing taxonomy preload.
14:55:28 7698 /wp-cron.php wp_cron_preload_cache: got 100 posts from position 0.
14:55:28 7698 /wp-cron.php supercache dir: /the-path-to/wp-content/cache/supercache/my-domain.com/blog/
14:55:28 7698 /wp-cron.php wp_cron_preload_cache: cancelling preload. stop_preload.txt found.
14:55:28 7698 /wp-cron.php URI rejected. Not Caching
14:55:28 7698 /wp-cron.php wp_cache_maybe_dynamic: returned $buffer
14:55:38 7737 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:55:38 7737 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:55:38 7737 /wp-admin/admin-ajax.php In WP Cache Phase 2
14:55:38 7737 /wp-admin/admin-ajax.php Setting up WordPress actions
14:55:38 7737 /wp-admin/admin-ajax.php Not caching wp-admin requests.
14:55:41 7738 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:55:41 7738 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:55:41 7738 /wp-admin/admin-ajax.php In WP Cache Phase 2
14:55:41 7738 /wp-admin/admin-ajax.php Setting up WordPress actions
14:55:41 7738 /wp-admin/admin-ajax.php Not caching wp-admin requests.
14:55:52 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:55:52 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:55:52 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload In WP Cache Phase 2
14:55:52 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload Setting up WordPress actions
14:55:52 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload Not caching wp-admin requests.
14:55:52 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload wpsc_cancel_preload: creating stop_preload.txt
14:55:56 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:55:56 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:55:56 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload In WP Cache Phase 2
14:55:56 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload Setting up WordPress actions
14:55:56 7739 /wp-admin/options-general.php?page=wpsupercache&tab=preload Not caching wp-admin requests.
14:56:16 7745 /wp-cron.php Removing auth from $_COOKIE to allow caching for logged in user (wordpress_logged_in_someClibberishCodeFragments123456789)
14:56:16 7745 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:16 7745 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:16 7745 /wp-cron.php In WP Cache Phase 2
14:56:16 7745 /wp-cron.php Setting up WordPress actions
14:56:16 7745 /wp-cron.php Created output buffer
14:56:16 7745 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:16 7745 /wp-cron.php supercache dir: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:16 7745 /wp-cron.php wpcache_do_rebuild: doing rebuild for /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:16 7745 /wp-cron.php wpcache_do_rebuild: exiting as directory is not a directory: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:23 7745 /wp-cron.php wp_cron_preload_cache: doing taxonomy preload.
14:56:23 7745 /wp-cron.php wp_cron_preload_cache: got 100 posts from position 0.
14:56:23 7745 /wp-cron.php supercache dir: /the-path-to/wp-content/cache/supercache/my-domain.com/blog/
14:56:23 7745 /wp-cron.php wp_cron_preload_cache: cancelling preload. stop_preload.txt found.
14:56:24 7745 /wp-cron.php URI rejected. Not Caching
14:56:24 7745 /wp-cron.php wp_cache_maybe_dynamic: returned $buffer
14:56:34 7745 /wp-cron.php Removing auth from $_COOKIE to allow caching for logged in user (wordpress_logged_in_someClibberishCodeFragments123456789)
14:56:34 7745 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:34 7745 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:34 7745 /wp-cron.php In WP Cache Phase 2
14:56:34 7745 /wp-cron.php Setting up WordPress actions
14:56:34 7745 /wp-cron.php Created output buffer
14:56:34 7745 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:34 7745 /wp-cron.php supercache dir: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:34 7745 /wp-cron.php wpcache_do_rebuild: doing rebuild for /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:34 7745 /wp-cron.php wpcache_do_rebuild: exiting as directory is not a directory: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:34 7745 /wp-cron.php URI rejected. Not Caching
14:56:34 7745 /wp-cron.php wp_cache_maybe_dynamic: returned $buffer
14:56:46 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:56:46 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:56:46 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload In WP Cache Phase 2
14:56:46 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload Setting up WordPress actions
14:56:46 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload Not caching wp-admin requests.
14:56:46 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload wpsc_cancel_preload: creating stop_preload.txt
14:56:51 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:56:51 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:56:51 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload In WP Cache Phase 2
14:56:51 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload Setting up WordPress actions
14:56:51 7753 /wp-admin/options-general.php?page=wpsupercache&tab=preload Not caching wp-admin requests.
14:56:56 7753 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:56:56 7753 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:56:56 7753 /wp-admin/admin-ajax.php In WP Cache Phase 2
14:56:56 7753 /wp-admin/admin-ajax.php Setting up WordPress actions
14:56:56 7753 /wp-admin/admin-ajax.php Not caching wp-admin requests.
14:56:57 7753 /wp-cron.php Removing auth from $_COOKIE to allow caching for logged in user (wordpress_logged_in_someClibberishCodeFragments123456789)
14:56:57 7753 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:57 7753 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:57 7753 /wp-cron.php In WP Cache Phase 2
14:56:57 7753 /wp-cron.php Setting up WordPress actions
14:56:57 7753 /wp-cron.php Created output buffer
14:56:57 7753 /wp-cron.php wp_cache_get_cookies_values: return:
14:56:57 7753 /wp-cron.php supercache dir: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:57 7753 /wp-cron.php wpcache_do_rebuild: doing rebuild for /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:57 7753 /wp-cron.php wpcache_do_rebuild: exiting as directory is not a directory: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:56:57 7753 /wp-cron.php URI rejected. Not Caching
14:56:57 7753 /wp-cron.php wp_cache_maybe_dynamic: returned $buffer
14:57:10 7757 /wp-cron.php Removing auth from $_COOKIE to allow caching for logged in user (wordpress_logged_in_someClibberishCodeFragments123456789)
14:57:10 7757 /wp-cron.php wp_cache_get_cookies_values: return:
14:57:10 7757 /wp-cron.php wp_cache_get_cookies_values: return:
14:57:10 7757 /wp-cron.php In WP Cache Phase 2
14:57:10 7757 /wp-cron.php Setting up WordPress actions
14:57:10 7757 /wp-cron.php Created output buffer
14:57:10 7757 /wp-cron.php wp_cache_get_cookies_values: return:
14:57:10 7757 /wp-cron.php supercache dir: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:57:10 7757 /wp-cron.php wpcache_do_rebuild: doing rebuild for /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:57:10 7757 /wp-cron.php wpcache_do_rebuild: exiting as directory is not a directory: /the-path-to/wp-content/cache/supercache/my-domain.com/wp-cron.php/
14:57:18 7757 /wp-cron.php wp_cron_preload_cache: doing taxonomy preload.
14:57:18 7757 /wp-cron.php wp_cron_preload_cache: got 100 posts from position 0.
14:57:18 7757 /wp-cron.php supercache dir: /the-path-to/wp-content/cache/supercache/my-domain.com/blog/
14:57:18 7757 /wp-cron.php wp_cron_preload_cache: cancelling preload. stop_preload.txt found.
14:57:18 7757 /wp-cron.php URI rejected. Not Caching
14:57:18 7757 /wp-cron.php wp_cache_maybe_dynamic: returned $buffer
14:57:20 7760 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: /^wp-postpass_someClibberishCodeFragments123456789|^comment_author_someClibberishCodeFragments123456789|^wordpress_logged_in_someClibberishCodeFragments123456789/ Cookie detected: wordpress_logged_in_someClibberishCodeFragments123456789
14:57:20 7760 /wp-admin/admin-ajax.php wp_cache_get_cookies_values: return: e13988922b4c1e1113cb103b175c8687
14:57:20 7760 /wp-admin/admin-ajax.php In WP Cache Phase 2
14:57:20 7760 /wp-admin/admin-ajax.php Setting up WordPress actions
14:57:20 7760 /wp-admin/admin-ajax.php Not caching wp-admin requests.

```

Start with the /wp-cron.php and /wp-admin/options-general.php?page=wpsupercache&tab=preload traces, then inspect wp_cron_preload_cache and wpsc_cancel_preload using the supplied log. Reproduce the multisite preload flow with the system cron command. Done means the preload starts and progresses without requiring repeated button clicks, and the initial and finish emails reflect the actual run.

Written by the indexing model from the issue text.