Wordpress LScache Plugin: Plugin could not be activated because it triggered a fatal error.
Last Updated on: Wed, 15 Apr 2026 00:00:02 Just a heads up. Ran into this on a new install, where it would not install with error: The plugin does not have a valid header. So I played with it a bit, try different ways to install. Once I finally got the install to work without error, it popped up a more understandable message: Plugin could not be activated because it triggered a fatal error. advanced-cache.php detected in wp-content directory! Please disable or uninstall any other cache plugins before enabling LiteSpeed Cache. Ahh, now we are onto something? So finally managed to get install working without errors. But sadly, server admin chose to not pay the extra duckets for the LSCache. Notice: Your installation of LiteSpeed Web Server does not have LSCache enabled. This plugin will NOT work properly. Oh well. https://wordpress.org/plugins/litespeed-cache/ Hi there, How did you download the plugin? I did some googling and it looks like one of the causes may be that files were installed in a sub directory (e.g. /litespeed-cache/litespeed-cache/ ) Id like to know the steps you took so we could provide better instructions on how to install the plugin. Cheers, Kevin Re: The plugin does not have a valid header. I simply installed from the repository and the error appeared. Giving up on that, because I was thinking something in the coding of your plugin was causing the error, I then used the download, then upload option, which then presented the more understandable error: Plugin could not be activated because it triggered a fatal error. advanced-cache.php detected in wp-content directory! Please disable or uninstall any other cache plugins before enabling LiteSpeed Cache. So yes, the error appears to have been caused by my having previously installed a caching plugin, and resulting advanced-cache.php file. Deleting that file allowed me to complete install. That said, your how-to or FAQ should possibly explain that the plugin will not work without the paid LiteSpeed LSCache Addon likewise installed. Hi there, We apologize for any confusion that we may have caused. If downloading from svn, we recommend the following command if you are using linux: wget -q -r -nH --cut-dirs=2 --no-parent https://plugins.svn.wordpress.org/litespeed-cache/trunk/ --reject html -P ./litespeed-cache That command will get the latest version from the trunk and create a subdirectory litespeed-cache in the current directory. We will add this to our documentation. Regarding the LSCache Addon issue, we will clarify the FAQ entry to include this. Thank you for your feedback. Cheers, Kevin Hi, I got same issue Install the plugin from repository and the first activation will got error The plugin does not have a valid header. Try to activate it from installed plugins was successful, but clicking on plugin Setting, you will be noticed Notice: Your installation of LiteSpeed Web Server does not have LSCache enabled. This plugin will NOT work properly. Best, Hien Hi Hien, Thank you for reporting this. Regarding the installing from repo issue, it may be because there is an extra line at the top of the litespeed-cache/litespeed-cache.php file. It is already removed in the upcoming version, so hopefully that should be resolved. Regarding the second issue, what version of LiteSpeed Web Server are you currently using? The message should only appear if you are not using a compatible version. Thanks, Kevin Hi Kevin, I am using LSWS V6.9 (generated by phpinfo()) and LiteSpeed Plugin 1.0.6. Best, Hien BTW, my host provider declined to enable LSCache module for security reasons. I am not sure how come they said that but if it is true, then it is hard to use this plugin Hi Hien, Please email me your hosting provider and a link to your site. Perhaps we can clear things up regarding the security issue. My email is kfwu at litespeedtech dot com Cheers, Kevin Hi Kevin, I emailed you already, please check. Best, Hien Hi, Have received below error from plugin on my site kindly assist Notice: Your installation of LiteSpeed Web Server does not have LSCache enabled. This plugin will NOT work properly. [Moderator Note: Please start your own support request. Do not jump in on others threads. Thanks.] Hello there, Adding the following lines to your .htaccess file under your WordPress installation directory should resolve this error. CacheLookup public on Please let us know if does not fix the issue or you have any further problems. Regards, Rob Hi Rob, will try to update .htaccess file like this.. # BEGIN WordPress RewriteEngine on # END WordPress # BEGIN WordPress CacheLookup public on # END WordPress # BEGIN WordPress RewriteEngine On RewriteBase / RewriteRule ^index .php$ ? [L] RewriteCond % REQUEST_FILENAME !-f RewriteCond % REQUEST_FILENAME !-d RewriteRule . /index.php [L] or RewriteEngine on CacheLookup public on # BEGIN WordPress RewriteEngine On RewriteBase / RewriteRule ^index .php$ ? [L] RewriteCond % REQUEST_FILENAME !-f RewriteCond % REQUEST_FILENAME !-d RewriteRule . /index.php [L] # END WordPress Problem still persist ? Kindly assist. himanshu_ag: Please start your own support request do not hijack threads. Thanks. himanshu_ag: Taking another look at your site, it appears you are using an Apache web server. LiteSpeed Cache for WordPress requires a LiteSpeed Web Server license (or OpenLiteSpeed Web Server) to work as it works directly with the web server and its LSCache module. As a result this plugin does not work with Apache. If you are using LiteSpeed Web Server, please confirm that your license has the LSCache Standard option selected. If it does not, you can follow this wiki to enable it: https://www.litespeedtech.com/support/wiki/doku.php/litespeed_wiki:licenses:add-lscache If this does not resolve your issue or you have further questions, please start your own support request regarding this as requested above by sterndata and well continue this there. Regards, Rob ok ? and i am sorry to bothered you
LiteCache Rush: Speed comes from using less, not from doing it faster
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