Today I used the automated plug-in installer to install W3 Total Cache which resulted in my page doing nothing but spitting out a nasty error. Since I did not want to spend time debugging their plug-in and had immediately lost faith in them for not properly handling their errors I went ahead and nuked the folder in the plugins directory. That left me staring at this nasty error:
W3 Total Cache Error: some files appear to be missing or out of place [...]
Hmmm… “Not cool,” I thought to myself. At least it seemed to be confined to the admin panel and my site was now back up and running from the user’s perspective I still had to try and fix this error without taking down the site again.
The initial suggestion made by the error description was to delete advanced-cache.php from your wp-content folder. I went ahead and renamed it to advanced-cache.php.bak and was then told by the next error that I should delete db.php. At this point I decided to do some more research and see what my best options were, and for hte time being I reinstated the advanced-cache.php file from it’s backup.
My search results on disabling a plug-in through the database all told me to look in the wp_options table and under the active_plugins field. In there was a serialized array containing each of the active plugins. I searched for “w3” and removed everything between the semi-colons for that plugin:
Remove:
i:12;s:33:"w3-total-cache/w3-total-cache.php";
At the start of the active_plugins field is an a: with a number beside it, this is your total number of enabled plugins. None of the sites I had dug up on disabling a plugin from this table mentioned this and the typically suggested wiping the entire line out to just a:0:{} which is not necessary.
After updating that field I was still presented with a message suggesting I delete the cache file. So I did the same and backed up each file it told me to (instead of deleting, as it suggested). In the end three files needed to be backed up.
Disable and Backup Some Files:
mv advanced-cache.php mv advanced-cache.php.bak mv db.php db.php.bak mv object-cache.php object-cache.php.bak
After refreshing my admin panel I once was able to log in to manage the site. Crisis averted! After a few days when I’m confident my site is stable I will delete the backups.
A seasoned Senior Solutions Architect with 18 years of experience in technology design and implementation. Renowned for innovative solutions and strategic insights, he excels in driving complex projects to success. Outside work, he is a passionate fisherman and fish keeper, specializing in planted tanks.
Hi, Thanks so much for this post, it helped me fix my problem with moving from WAMP to online WordPress. I also found I needed to delete the W3 Total Cache plugin folder and reinstall it for it to work again otherwise the whole process would repeat.
Jen
I found you’re blog this morning after spending most of the early hours, trying to fix a similar problem with my site after installing the W3 Total Cache plugin.
I’m now where near as knowledgeable as you with WordPress as you obviously are, and was very concerned that I’d lost all my mental faculties and was unable of installing a simple plugin correctly.
My problem was that I was unable to upload any more images to my site without getting a ‘HTTP Error Code’.
I followed some instructions from the WordPress Forum and replaced the image files wp-uploads folder and wp-includes folder.
This was when I lost all visibility of my site. Due to my in experience I had to get ‘Bluehost’ to sort the problem out for me. It’s all up and running again now, minus a few links to some images. But what a pain in the backside. Lesson learned though. I won’t be activating any more plugins until I research them thoroughly first.