Title: Error during plugin activation
Last modified: October 19, 2021

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# Error during plugin activation

 *  Resolved [tobyhage](https://wordpress.org/support/users/tobyhage/)
 * (@tobyhage)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/error-during-plugin-activation-3/)
 * I am using WP Multisite in Cyberpanel. WordPress is working fine without the 
   LSCache plugin but when I try to install LSCache it throws this error.
 * `PHP Fatal error: Uncaught Error: Undefined constant "LiteSpeed\COOKIEHASH" in/
   wp-content/plugins/litespeed-cache/src/htaccess.cls.php:528`
 * Any help is appreciated.
 * See also: [https://wordpress.org/support/topic/error-during-plugin-activation-2/](https://wordpress.org/support/topic/error-during-plugin-activation-2/)
    -  This topic was modified 4 years, 7 months ago by [tobyhage](https://wordpress.org/support/users/tobyhage/).
    -  This topic was modified 4 years, 7 months ago by [tobyhage](https://wordpress.org/support/users/tobyhage/).
    -  This topic was modified 4 years, 7 months ago by [tobyhage](https://wordpress.org/support/users/tobyhage/).

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Plugin Support [qtwrk](https://wordpress.org/support/users/qtwrk/)
 * (@qtwrk)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/error-during-plugin-activation-3/#post-14986643)
 * please edit that file , add
 * `error_log( print_r(COOKIEHASH, TRUE), 3 , "/your_path_to/public_html/lscwp.log");`
 * after line 528 $vary_cookies[] = ‘,wp-postpass_’ . COOKIEHASH;
 * now do it again , see what does it show in /your_path_to/public_html/lscwp.log
 * are you running OpenLiteSpeed with it ?
 *  Thread Starter [tobyhage](https://wordpress.org/support/users/tobyhage/)
 * (@tobyhage)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/error-during-plugin-activation-3/#post-14989823)
 * Hello,
 * Thank you for you’re reply.
 * You’re instructions are a little bit short.
 * I have added the error log on the last line of the file htaccess.cls.php
    and
   added the line
 * $vary_cookies[] = ‘,wp-postpass_’ . COOKIEHASH;
 * after line 528. But that line was already there, so it is now written two times.
 * the log file contains ffbddc434c0af204c7a9a32562f3126f
 * Yes i run openlitespeed.
 *  Plugin Support [qtwrk](https://wordpress.org/support/users/qtwrk/)
 * (@qtwrk)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/error-during-plugin-activation-3/#post-14990523)
 * okay , now that is interesting
 * because as you can see , it logs out the COOKIEHASH , which means it is defined,
   so why the PHP complaints undefined constant ?
 * please create a ticket by mail to `support at litespeedtech.com` with reference
   link to this topic , we will investigate further
 * Best regards,

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘Error during plugin activation’ is closed to new replies.

 * ![](https://ps.w.org/litespeed-cache/assets/icon-256x256.png?rev=2554181)
 * [LiteSpeed Cache](https://wordpress.org/plugins/litespeed-cache/)
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 * 3 replies
 * 2 participants
 * Last reply from: [qtwrk](https://wordpress.org/support/users/qtwrk/)
 * Last activity: [4 years, 7 months ago](https://wordpress.org/support/topic/error-during-plugin-activation-3/#post-14990523)
 * Status: resolved