The use of caching plugins for WordPress is a massive win in terms of performance. But they can also be a headache for webmasters who fail to see the changes they make to their site show up.
One of the most common issues people have when using Divi Booster is that their changes aren't applied. The culprit more often than not is that an old (pre-change) version of the page has been stored and is being shown to the user, instead of the nice new one.
This post is a work-in-progress attempt to help you identify and solve some common caching problems. I hope this will get you to an answer quicker and same me tearing my hair out quite so often.
Detecting a Caching Issue
The following can help you figure out if you have a caching issue:
- The first sign that there may be a caching issue is that you attempt to make a change to the site (with Divi Booster or something else) and it doesn't show up. This doesn't guarantee that it's a caching issue – the problem could be a bug or CSS conflict, etc – but it should be a bit of a warning sign.
- In this situation, compare what you see when you're logged out vs logged in. Some caching plugins always show the latest copy of the page to logged in users (so they can see their changes), but then show old copies to the user (for performance). If you see the change when logged in, but it disappears when you log out you've almost certainly got a caching issue.
- Another test is to go to your site homepage, right click and select "View page source". This shows you the HTML code of the page. Scroll down to the bottom and you may see a HTML comment which tells you that the page was generated by a particular plugin at a particular time. Something like this:
<!-- Cached page generated by WP-Super-Cache on 2015-01-24 20:31:10 -->
The mere presence of this is enough to tell you that your page is probably being cached, but if you check the date and time given you may see for certain that the page was generated prior to you making the changes (in which case your changes wouldn't be shown on the page). Note that the time will be in your server's timezone, not necessarily your own.
Clearing your Caches
The immediate solution to a caching problem is to clear your caches. Doing so will force your site to generate a new copy of the page which should include your Divi Booster or other updates. The trick is knowing which caches you have.
- The first place to look is in your installed plugins. Go through the list of active plugins and any whose purpose is to speed up your site (e.g. WP Super Cache, W3 Total Cache, etc) are likely to perform caching and should have an option to clear (or "flush") their caches. If you can't see an option to clear the caches you may want to disable these plugins temporarily to see if they are the problem.
- Next look at whether you are using any site enhancing services such as CloudFlare. If so, log into your admin panel for these services (often through their own site) and look for an option to clear their caches.
- Now visit your site in your browser, and see if your changes have shown up.
- If so, great. If not there is one more thing to try – clearing your browser's cache. To do so, press CTRL-shift-delete (in most browsers) or locate the "clear history" feature using your browser's menu. Select to clear everything, making sure that any option to clear the caches is included in this. This will get rid of any old copies of the webpage that your browser is using.
- Reload your site in your browser. Hopefully the changes will now show up. If not, give me a shout and I'll try to get the issue sorted.
Here is an incomplete list of products which perform caching and if you use any of them I suggest clearing their caches to see if that allows the Divi Booster changes to show up:
- W3 Total Cache
- WP Super Cache
- CloudFlare (via cloudflare.com login)