Please Note: This wiki is no longer valid for modern versions of LiteSpeed Cache for WordPress. Additionally, LSCWP documentation has moved to a new location.
LiteSpeed Cache for WordPress sometimes encounters errors. Explanations and possible solutions to these codes are listed below. If the suggested courses of action don't solve your problem, please do not hesitate to contact us via the plugin's support forum.
LSCWP has minimum requirements for the software on which it relies. These error codes pop up when the software fails to meet these requirements.
The installed PHP version is too old for the LiteSpeed Cache Plugin. The LiteSpeed Cache Plugin requires at least PHP 5.3. The currently installed version is PHP <PHP_VERSION>, which is out-dated and insecure. Please upgrade or go to active plugins and deactivate the LiteSpeed Cache plugin to hide this message.
Upgrade the PHP version used. If needed, set up a new PHP version as described here.
Select an upgraded PHP version if possible. If not, please contact the server administrator for options.
The installed WordPress version is too old for the LiteSpeed Cache Plugin. The LiteSpeed Cache Plugin requires at least WordPress 3.3. Please upgrade or go to active plugins and deactivate the LiteSpeed Cache plugin to hide this message.
Upgrade to the latest version of WordPress.
These codes relate to errors that occur during cache management tasks.
Something went wrong with the form! Please try again.
Something went wrong when attempting to submit the purge action. Refresh the page and try again.
Tried to purge list with empty list.
The Purge List button was pressed but the Purge By… box was empty. Please enter a list of categories, tags, or URLs, on per line, and try again.
Bad Purge By selected value.
Somehow, an invalid Purge By type was selected. Refresh the page and try again.
Failed to purge by category, invalid category slug.
Purging by category requires the category slug. You can find a category's slug in the category list found at Posts > Categories. Or, if you know the category's URL, you can get the slug from that. In http://www.example.com/category/my-category the slug would be my-category.
Failed to purge by tag, invalid tag slug.
Purging by tag requires the tag slug. You can find a tag's slug in the category list found at Posts > Tags. Or, if you know the tag's URL, you can get the slug from that. In http://www.example.com/tag/my-tag the slug would be my-tag.
Failed to purge by url, contained "<".
One or more of the URLs listed contained a <. This is strictly forbidden. Please try listing the URLs again, making sure to avoid using this character.
Failed to purge by Post ID, given ID is not numeric: <ID>
One or more of the Post IDs listed is not numeric. Every post has an ID that is a number. Please try listing the IDs again, making sure that all IDs listed are numeric.
Failed to purge by Post ID, given ID does not exist or is not published: <ID>
One or more of the Post IDs listed does not exist or the post is not published. Please verify that the correct Post ID was used. Check Posts > All Posts and hover over the title of the post in question. You should be able to get the ID from the URL.
Failed to purge by URL, invalid input: <URL>
You may purge by URI or full URL, that is, /2016/02/24/hello-world/ or http://www.myexamplesite.com/2016/02/24/hello-world/. If your URL is in any other format, it will be rejected.
Failed to purge by category, does not exist: <CATEGORY>
The category specified doesn't exist. Visit Posts > Categories to verify that you've entered the correct category slug.
Failed to purge by tag, does not exist: <TAG>
The tag specified doesn't exist. Visit Posts > Tags to verify that you've entered the correct tag slug.
The following error codes are related to problems with data entered into various Settings fields.
Invalid data in Admin IPs.
The Admin IPs setting on the Debug tab allows you to specify IPs that may perform certain admin actions from their browsers. This error indicates that one or more of the entered IP addresses is invalid. Double-check the IPs and try again.
Invalid data in Test IPs.
This error message has been deprecated. If you are seeing this, you are using a version of LSCWP that is pretty old! Why not update?
Invalid Site IP: <IP ADDRESS>
The IP address you entereed, <IP ADDRESS>, is not valid. Check your site's IP and try again.
Can not fetch Custom Sitemap: http://www.example.com/sitemapfile.xml
The sitemap file name you entered is invalid or the file is unavailable. Double-check the URL and try again. Be sure that you are entering the full URL to the file.
Can not parse custom sitemap xml file: http://www.example.com/sitemapfile.xml.
The sitemap file was fetched but cannot be read. Make sure the sitemap is in XML format and that you have installed the php-xml extension on your server.
<CONTENT TYPE> TTL must be an integer between <MINIMUM> and 2147483647.
The <CONTENT TYPE> Time To Live entered was either not an integer or did not fit within the range listed. Please try a different value. TTL is the time in seconds before a given type of content expires. Most of these settings list a valid range in their tool tips, so be sure to read them.
Removed category "<CATEGORY>" from list, ID does not exist.
Categories are listed one-per-line by slug. One <CATEGORY> you entered wasn't found, and so it was removed from the Do Not Cache Categories list. You can find a category's slug in the category list found at Posts > Categories. Or, if you know the category's URL, you can get the slug from that. In http://www.example.com/category/my-category the slug would be my-category.
Removed tag "<TAG>" from list, ID does not exist.
Tags are listed one-per-line by slug. One <TAG> you entered wasn't found, and so it was removed from the Do Not Cache Tags list. You can find a tag's slug in the tag list found at Posts > Tags. Or, if you know the tag's URL, you can get the slug from that. In http://www.example.com/category/my-tag the slug would be my-tag.
Invalid login cookie. Invalid characters found: <LOGIN COOKIE>
<LOGIN COOKIE> has invalid characters. Try again, entering a login cookie value that contains only alphanumeric characters, _, or -. You can make up any string you like for this setting, as long as it contains valid characters.
Invalid Rewrite List. Empty or invalid rule. Rule: <OPTION>, list: <LIST>
This error is used with pairs of settings such as Cache Mobile and List of Mobile User Agents. One setting is the ON/OFF switch (<OPTION>), while the other setting gives the parameters (<LIST>) for the switch when it is turned ON.
If this message is displayed, that means that the list entered is not valid for the option that has been enabled.
If <LIST> is blank, that means the rule expected some parameters to be defined, but none were.
Errors in the this range are related to various problems reading, writing, or interpreting configuration files stored on disk.
Tried to parse for existing login cookie. .htaccess file not valid. Please verify contents.
On upgrade, we check to see if a login cookie was manually inserted. If the .htaccess file is corrupted in any way, this warning will output. This may indicate mismatched tags.
Could not find <CONTENT>.
Receiving this error message means that the .htaccess file was modified in an unexpected manner, which resulted in missing tags, rules, or comments that are expected to be there. The easiest way to resolve this is to:
.htaccess file LSCACHE START PLUGIN/LSCACHE END PLUGIN comments and those comments themselves..htaccess.This should fix the problem.
This site is a subdirectory install. Login cookies do not match. Please remove both and set the login cookie in LiteSpeed Cache advanced settings.
On upgrade, we check to see if a login cookie was manually inserted. The plugin detected that this was a subdirectory install and determined that the login cookie for the two .htaccess files did not match.
To fix this problem, remove the login cookies from both installs and set again in LiteSpeed Cache > Settings > Advanced.
Notice: This plugin requires a LiteSpeed Server with the LSCache Module enabled. If you are unable to change your server stack, please contact your hosting provider to request the required changes. This plugin will NOT work properly.
This plugin requires a LiteSpeed Server with the LSCache Module enabled, and will not function without one.
If a LiteSpeed Server is already installed, it may just require switching from Apache to LiteSpeed. Note: If the license that is being used is not at least a 2-CPU license, then the LSCache Module may be not included. In this case, either upgrade the license to a 2-CPU+ license or purchase the LSCache Module addon.
As a LiteSpeed Server is required, please contact the server admin for the possibility of switching to a LiteSpeed Server.
LiteSpeed Cache was unable to write to the wp-config.php file. Please add the following to the wp-config.php file: define('WP_CACHE', true);.
Check the wp-config.php file permissions. This error indicates that we attempted to set WP_CACHE to true, but was unable to write to the file.
You can either change the permissions on wp-config.php and try again, or you can manually add the line define('WP_CACHE', true); to the file.
Failed to back up file, aborted changes.
Before making any changes to the .htaccess file, the plugin always creates a backup. If the backup fails, you see this error, and the changes are aborted.
Check the permissions of the WordPress root and .htaccess files to make sure that the directory/files are writable.
Failed to put contents into .htaccess.
The plugin attempted to make changes to the .htaccess file, but was unable to successfully save the file. Please check the permissions of the WordPress root and .htaccess files to make sure that the directory/files are writable.
Failed to get .htaccess file contents.
The plugin attempted to read the .htaccess file, but was unable to open it. Please check the permissions of the WordPress root and .htaccess files to make sure that the directory/files are readable.
.htaccess file not readable or not writable.
The plugin attempted to read or write to the .htaccess file, however in checking the file permissions, it returned either not readable or not writable. Please check the permissions of the WordPress root and .htaccess files to make sure that the directory/files are readable.
.htaccess file not readable.
The plugin attempted to read the .htaccess file, however in checking the file permissions, it returned not readable. Please check the permissions of the WordPress root and .htaccess files to make sure that the directory/files are readable.
.htaccess file not writable.
The plugin attempted to write to the .htaccess file, however in checking the file permissions, it returned not writable. Please check the permissions of the WordPress root and .htaccess files to make sure that the directory/files are writable.
Prefix was found after suffix.
Receiving this error message means that the .htaccess file was modified in an unexpected manner, which resulted in missing tags, rules, or comments that are expected to be there. The easiest way to resolve this is to:
.htaccess file LSCACHE START PLUGIN/LSCACHE END PLUGIN comments and those comments themselves..htaccess.This should fix the problem.
Failed to overwrite .htaccess.
The plugin attempted to make changes to the .htaccess file, but was unable to successfully save the file. Please check the permissions of the WordPress root and .htaccess files to make sure that the directory/files are writable.
The wp-config file not writeable for 'WP_CACHE'.
Check the wp-config.php file permissions. This error indicates that we attempted to set WP_CACHE to true, but were unable to write to the file.
wp-config file did not find a place to insert define.
This error indicates that there is a custom wp-config.php set up. Manually add the define in the desired customized location. A suggested location is just above where $table_prefix is set. If this is beyond your comfort level, contact us via the plugin's support forum.