WP Super Cache – Caches Category Page Instead of Home Page

I’ve given up trying to fix this bug as I don’t have time to arrange getting logins, ftping files, editing and tracking changes to the front page. “Half-on” mode is practically as fast so unfortunately it’ll remain the only fix for this stubborn but elusive bug.

If you want to debug it yourself:
1. Monitor the front page of your blog by firing a request at it every few seconds.
2. Search for a string that is on the category page that sometimes shows up.
3. If that string is found send an email to yourself.
4. Check your access logs for the period between the last check and the one that alerted you for any suspicious requests (for any value of “suspicious”, I don’t know what it is)
5. Try setting it off yourself using a not logged in browser and the requests that were recorded preceeding the alerting check.
6. Email me when you know how it happens and I’ll fix it.

I gotta rename “half-on” mode to “PHP mode” or something. There’s negligible difference between it and static caching.

Kinda sad to hear that but oh well.

Donncha, one question: what is faster in your estimation… 0.7.1 in full mode or the current version 0.9.6 in full mode?

I doubt there’s much difference. Maybe milliseconds because of the extra mobile user agent checks? Certainly not measurable.

Good question, Mantis, I was wondering the same thing.

Donncha, this might not be much help but I never saw the problem myself until Google misindexed the home page and others complained. All my browsers that had a site cookie set behaved fine, it was only total strangers (aka virtually everyone else) that saw the bad home page.

blakekr – milliseconds, if any. they’re the same speed.

What you saw is what others have seen. Only users seeing the supercached pages get the wrong cached page. I don’t know why that happens ??

I almost switched to WP after even worse issues in Joomla, but you are making me think again now. In order to have SEF URLs, we had a component issue creating URLs that were actually non existent so that Google indexed non existing pages and kept reporting 404 error each crawling. It was building up to more than 900 pages and we finally decided to kill the component to be SE friendly again. Now, since mattcutts talked me into WP here is an issue that I would hate to face, so please report here if anyone cured this problem. Thanks.

Lazarevac – out of tens of thousands of blogs using WP Super Cache this happens to a handful and is fixed by switching to half on mode that is just as fast.

I can’t reproduce it on any of my sites so I’m going to have to depend on someone else tracking down why it happens. If it was a common problem that would happen.

I’m having this same problem and I have to say that I’m not necessarily sure this happens to just a “handful of blogs”. Personally, I think it could be happening to a lot of blogs, but they just don’t know it.

For example, on my website, I didn’t see this problem on any of my home computers or office computers. Only when I traveled to another city and loaded my website on a friends computer did I see the category page as the home page.

Also, after a couple of hours, the problem disappeared on that computer. This problem is so hard to reproduce and to detect that it could easily have been happening to my site for months without me having any idea.

aseem1234 – I disagree, I think it’s a few. I couldn’t reproduce it but I included a warning in the readme.txt. It only affects users who have configured WordPress in a particular way, and even then, only some of them.

When I configured ocaoimh.ie that way I set up a script that monitored the blog every minute and for several days it never once occurred on my blog.

Unless someone with a blog that it affects can find a solution, the only solution is to use the plugin in half-on mode (which is the same thing that every other single page caching plugin for WordPress does so it’s pretty good!)

Hi Donncha, so how do you know how many users have blogs that are configured in this certain way that causes the problem? If you don’t know what configuration is causing the problem in the first place, how can you know how many people actually have this configuration for WordPress?

Maybe you could write up a questionnaire and send that to all the people you know are having this issue and then see what is possibly common between them. I would think this might get you the answer quicker than us trying random stuff. (What plugins is everyone using, permalinks or not, shared hosting or dedicated, etc, etc)

aseem – see the section titled “A category page is showing instead of my homepage” in the readme.txt. That’s the configuration that everyone who has had this problem has. It’s not a common one.

That doesn’t matter anyway because I can’t replicate it, and the people who do have the problem don’t have the skills required to fix it. ??

Ahhh OK, that makes more sense, there is an underlying reason for it. Hmm, so my having /category/post-title is what causes this issue.

What exactly do you need to do in order to debug this? What skills are required to fix it? Maybe I can help. I have a tech friend who knows Linux, Apache, PHP and WordPress very well (what my server is running).

Do you have a static page for your front page too?

Skills? Just general PHP and WP skills. Someone who knows how to use error_log or can use the debug functions in supercache and the patience to track down the error.

Grab the development version from the download page – it has an advanced debug setting that monitors the front page of your blog once a minute and reports and/or clears the cache when the front page goes wrong. Try that and examine your access log to see if anything unusual triggers the problem. (No, I don’t know what something unusual is!)

No I don’t have a static front page, just the permalinks structure you mentioned. I will go ahead and try to see if I can find anything! Thanks!

Hi, i have a same problems ?? i want to uninstalled w3 total cache plugins and want to install hyper cache plugins.

After i’m uninstalled the w3 total cache on the web directory, edit the wp-config.php and deleted on w3tc table on wordpress database

I got error message like this:

Warning: Cannot modify header information – headers already sent by (output started at /home/neotech-r3.com/public_html/wp-content/themes/magatheme/functions.php:48) in /home/neotech-r3.com/public_html/wp-includes/pluggable.php on line 865

I was googling but still not found how to figure it out this problems.

Perhaps someone could help me.