Title: define(‘WP_CACHE’, true); error message Last modified: May 8, 2018 --- # define(‘WP_CACHE’, true); error message * Resolved [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/) * Hi, * I noticed an error something like that said WP super cache is installed so search for solution and found a post about WP super cache and Hummingbird compatibility, then learned no need to have both of them so cleared cache and deactivated WP super cache. * My site still looks working fine but got another error message in the Page Caching page, Hummingbird could not locate the WP_CACHE constant in wp-config.php file for WordPress. Please make sure the following line is added to the file: define(‘ WP_CACHE’, true); * I don’t know if it is affecting negatively on my site but what would be proper solution for that error message? I deactivated WP super cache but didn’t delete it completely yet. * Please help. * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fdefinewp_cache-true-error-message%2F%3Foutput_format%3Dmd&locale=en_US) to see the link]_ Viewing 15 replies - 1 through 15 (of 20 total) 1 [2](https://wordpress.org/support/topic/definewp_cache-true-error-message/page/2/?output_format=md) [→](https://wordpress.org/support/topic/definewp_cache-true-error-message/page/2/?output_format=md) * [Anton Vanyukov](https://wordpress.org/support/users/vanyukov/) * (@vanyukov) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257295) * Hi [@sailors](https://wordpress.org/support/users/sailors/), * You are correct – both Hummingbird and WP Super Cache should not be used together. In fact, any plugins or settings that do the same thing should not be used together. * Regarding the message, please make sure that define(‘WP_CACHE’, true); is present in the wp-config.php file. If it’s not there, you can add it manually via any FTP editor. * Best regards, Anton * Thread Starter [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257332) * Thank you for your very quick reply, Anton. * I just added define(‘WP_CACHE’, true); in the wp-config.php file, and cleared cache but still get that same error message. * [Anton Vanyukov](https://wordpress.org/support/users/vanyukov/) * (@vanyukov) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257348) * [@sailors](https://wordpress.org/support/users/sailors/), * It seems that Hummingbird is not seeing it. Could you please remove it, deactivate Hummingbird page caching and activate it again. After that check if WP_CACHE is defined in wp-config.php. You should see a // Added by WP Hummingbird comment right next to it. * Best regards, Anton * Thread Starter [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257379) * I still get that error. * I followed your instruction and don’t see the Hummingbird comment in wp-config. php. Do I need to deactivate the Hummingbird plugin instead of just the page caching? * Thread Starter [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257386) * BTW, I have Autoptimize plugin installed. Does it matter? I cleared that cache, too when following your instruction. * [Anton Vanyukov](https://wordpress.org/support/users/vanyukov/) * (@vanyukov) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257391) * [@sailors](https://wordpress.org/support/users/sailors/), * It shouldn’t really matter, as long as the WP_CACHE constant is defined to TRUE, all should be fine. What are your file permissions for wp-config.php? And are you using any special installation of WordPress (Bedrock, for example)? * Best regards, Anton * Thread Starter [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257403) * The file permission for wp-config.php is 644. I don’t use any special installation of WP. I’m not that technical. * [Anton Vanyukov](https://wordpress.org/support/users/vanyukov/) * (@vanyukov) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257436) * [@sailors](https://wordpress.org/support/users/sailors/), * Are you using any security plugins? * Best regards, Anton * Thread Starter [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257586) * I deactivated Wordfence and tried again, and still see the error message. Do I need to delete WP Super Cache from my plugin list? * Thread Starter [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257667) * Also, the site language is set to Japanese so all sentences other than codes in the wp-config.php are Japanese. * [Anton Vanyukov](https://wordpress.org/support/users/vanyukov/) * (@vanyukov) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10257703) * [@sailors](https://wordpress.org/support/users/sailors/), * The language and deactivated plugins should not be making a difference. * Could you please contact me via this contact form: [https://premium.wpmudev.org/contact/](https://premium.wpmudev.org/contact/) Select “I have a different question” In subject please add “Attn: Anton” so that the message is assigned to me. Also, please link to this thread for reference. * Best regards, Anton * Thread Starter [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [8 years ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10286679) * Just wondering what’s going on after that. Any updates? * Plugin Support [Dimitris – WPMU DEV Support](https://wordpress.org/support/users/wpmudev-support6/) * (@wpmudev-support6) * [7 years, 12 months ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10291541) * Hello there [@sailors](https://wordpress.org/support/users/sailors/) * Have you sent an email to Anton already? Because I’ve searched our inbox for subject _“Attn: Anton”_ and/or the URL of this topic and couldn’t locate any. Please advise! * Warm regards, Dimitris * Thread Starter [sailors](https://wordpress.org/support/users/sailors/) * (@sailors) * [7 years, 12 months ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10291832) * Thanks for your reply, Dimitris. * Yes, I sent an Email right after he told me to do so. Should I send again? * Plugin Support [Dimitris – WPMU DEV Support](https://wordpress.org/support/users/wpmudev-support6/) * (@wpmudev-support6) * [7 years, 12 months ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/#post-10294723) * Hello [@sailors](https://wordpress.org/support/users/sailors/) * It seems that we haven’t received anything so far. Could you please send an email, using our safe contact [https://premium.wpmudev.org/contact/#i-have-a-different-question](https://premium.wpmudev.org/contact/#i-have-a-different-question) * Please set as subject “**Attn: Anton**” and include the URL of this topic. [https://wordpress.org/support/topic/definewp_cache-true-error-message/](https://wordpress.org/support/topic/definewp_cache-true-error-message/) * Feel free to post back here, when this is done, so we could double check quickly! 🙂 * Warm regards, Dimitris Viewing 15 replies - 1 through 15 (of 20 total) 1 [2](https://wordpress.org/support/topic/definewp_cache-true-error-message/page/2/?output_format=md) [→](https://wordpress.org/support/topic/definewp_cache-true-error-message/page/2/?output_format=md) The topic ‘define(‘WP_CACHE’, true); error message’ is closed to new replies. * ![](https://ps.w.org/hummingbird-performance/assets/icon-256x256.gif?rev=2633221) * [Hummingbird Performance - Cache & Page Speed Optimization for Core Web Vitals | Critical CSS | Minify CSS | Defer CSS Javascript | CDN](https://wordpress.org/plugins/hummingbird-performance/) * [Frequently Asked Questions](https://wordpress.org/plugins/hummingbird-performance/#faq) * [Support Threads](https://wordpress.org/support/plugin/hummingbird-performance/) * [Active Topics](https://wordpress.org/support/plugin/hummingbird-performance/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/hummingbird-performance/unresolved/) * [Reviews](https://wordpress.org/support/plugin/hummingbird-performance/reviews/) ## Tags * [page caching](https://wordpress.org/support/topic-tag/page-caching/) * 20 replies * 4 participants * Last reply from: [calumbrash](https://wordpress.org/support/users/calumbrash/) * Last activity: [7 years, 12 months ago](https://wordpress.org/support/topic/definewp_cache-true-error-message/page/2/#post-10302527) * Status: resolved