Caching of your wordpress files is very important to reduce the server and database load, especially in shared hosting scenarios. WP-Supercache, the next generation of WP-Cache is a powerful wordpress caching plugin.
WP-Cache 2 is a popular plugin that caches the pages of your WordPress blog and delivers them without accessing the database, but it still means loading the PHP engine to serve the cached files; WP Super Cache gets around that by generating html files that are served without invoking a single line of PHP!
WP-Cache had problems working on this blog and always ended up bringing the site down. After this site overloaded servers, I had to try installing WP-supercache to see if might work. The installation and activation went without a hitch, the blog was loading fine, but no pages were being cached!
WordPress Super Cache Not Working?
I looked up the Troubleshooting page and here is the checklist.
- Is wp-content writable by the web server?
Yes. Looked for file permissions. All OK
- Is there a wp-content/wp-cache-config.php ?
I deleted it earlier as preinstallation task (earlier installed by WP-cache). This was created there when plugin activated.
- Is there a wp-content/advanced-cache.php ?
I was unable to delete this linked file via FTP as a preinstallation task (earlier installed by WP-cache). But it was still there.
- Make sure the following line is in wp-config.php
define( 'WP_CACHE', true );
This entry was deleted from wp-config.php as a preinstallation task (earlier installed by WP-cache) and now it was recreated back in the same place.
- Try the Options->WP Super Cache page again and enable cache.
Done. OK. But the status is still same.
- Look in wp-content/cache/supercache/…
Something wrong. No files there. No folder there.
- Anything in your php error_log?
- If your browser keeps asking you to save the file…
Well Super Cache compression was disabled by default in the options and browser asked nothing.
- The plugin does not work when PHP’s safe mode is active.
Ok. No problems.
- Your blog can be viewed with and without the “www” prefix.
Blog set to view as www. No problem there.
Fix WP-Super-Cache Problems
Then I went about checking and here are the few tips that worked for me, and might work for you too.
1. No Supercache Folder – In #6 supercache folder was missing, so I had to manually create the folder as it was not there. I used FTP to login to my server using Filezilla and created wp-content/cache/supercache/. But still not working.
2. Change Settings – I tried working in HALF ON (Super Cache Disabled) mode, Super Cache Compression on and off mode, checked the .htaccess files for correct mod_rewrite rules (important to check!), but nothing worked.
2. Deleting advanced-cache.php. Then I realized that in #3, I was unable to delete advanced-cache.php. Though I believed the installation had rewritten on the linked file, it might have not.
The ealier wp-cache file was linked to wp-cache/wp-cache-phase1.php
but the supercache file should link to wp-super-cache/wp-cache-phase1.php
I thought this was the problem. But I was unable to delete it via FTP. So I used my newly acquired SSH skills and use PuTTY to get in and delete the file.
and the file was finally deleted. Disable and Activate the plugin, it generated a new advanced-cache.php with the new shortcut. I could have also tried
ln -s plugins/wp-super-cache/wp-cache-phase1.php advanced-cache.php
Guess what…. it started to work!!!
If that does not help you, look up the wordpress forums for more support.