Answers.Body: <p>Suspect this issue is happening when the site is accessed via <code>https://example.com</code> instead of <code>https://www.example.com</code>, or when moving from one domain to another midway through a form submission.</p>
  
  <p>See also <a href="https://civicrm.stackexchange.com/questions/12323/how-do-i-debug-could-not-find-valid-value-for-ct-error-message">this similar SE question</a>. This text is in the error message you've pasted:</p>
  
  <blockquote>
    <p>Site Administrators: This error may indicate that users are accessing this page using a domain or URL other than the configured Base URL. EXAMPLE: Base URL is <a href="http://example.org" rel="nofollow noreferrer">http://example.org</a>, but some users are accessing the page via <a href="http://www.example.org" rel="nofollow noreferrer">http://www.example.org</a> or a domain alias like <a href="http://myotherexample.org" rel="nofollow noreferrer">http://myotherexample.org</a></p>
  </blockquote>
  
  <p>Make sure both WordPress and CiviCRM have a matching URL configured - CiviCRM in <code>civicrm.settings.php</code>, WordPress in Settings ⇒ General admin page (ref <a href="https://codex.wordpress.org/Changing_The_Site_URL" rel="nofollow noreferrer">WP Codex: Changing the Site URL</a>). Ideally, make sure that anyone landing on alternate URLs is redirected immediately to the canonical hostname and protocol.</p>
  
  <p>The <code>.htaccess</code> snippet in this question addresses consistent protocol but not hostname.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-12-02T08:59:22.423Z
Answers.Text: Might the trailing slash in the URL ('https://www.domain.com/') of civicrm.settings.php cause the problem, which is not present in the wordpress settings ('https://www.domain.com')?
Answers.UserDisplayName: ajasper
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-08-14T09:43:32.763Z
Answers.LastActivityDate: 2016-08-14T09:49:53.577Z
Answers.LastEditDate: 2017-04-13T12:53:13.167Z
Answers.UserDisplayName: Chris Burgess
Body: <p>Event registration issues, reports from users make it seem to be with some regularity.</p>
  
  <p>Message mentions cookies but I am having trouble tracking this down, does anyone have any pointers about where to look?</p>
  
  <p>CiviCRM log has following:</p>
  
  <pre><code>    Aug 13 19:48:17  [info] $Fatal Error Details = Array
  (
      [message] =&gt; We can't load the requested web page. This page requires cookies to be enabled in your browser settings. Please check this setting and enable cookies (if they are not enabled). Then try again. If this error persists, contact the site administrator for assistance.&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;Site Administrators: This error may indicate that users are accessing this page using a domain or URL other than the configured Base URL. EXAMPLE: Base URL is http://example.org, but some users are accessing the page via http://www.example.org or a domain alias like http://myotherexample.org.&amp;lt;br /&amp;gt;&amp;lt;br /&amp;gt;Error type: Could not find a valid session key.
      [code] =&gt; 
  )
  
  
  Aug 13 19:48:17  [info] $backTrace = #0 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Error.php(371): CRM_Core_Error::backtrace("backTrace", TRUE)
  #1 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Controller.php(833): CRM_Core_Error::fatal("We can't load the requested web page. This page requires cookies to be enable...")
  #2 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Controller.php(853): CRM_Core_Controller-&gt;invalidKeyCommon()
  #3 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Event/Controller/Registration.php(66): CRM_Core_Controller-&gt;invalidKeyRedirect()
  #4 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Controller.php(312): CRM_Event_Controller_Registration-&gt;invalidKey()
  #5 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Controller.php(204): CRM_Core_Controller-&gt;key("CRM_Event_Controller_Registration", TRUE, FALSE)
  #6 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Event/Controller/Registration.php(45): CRM_Core_Controller-&gt;__construct("Event Registration", "null")
  #7 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(307): CRM_Event_Controller_Registration-&gt;__construct("Event Registration", TRUE, "null", NULL, "false")
  #8 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(86): CRM_Core_Invoke::runItem((Array:15))
  #9 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(54): CRM_Core_Invoke::_invoke((Array:3))
  #10 /var/www/html/wp-content/plugins/civicrm/civicrm.php(1227): CRM_Core_Invoke::invoke((Array:3))
  #11 [internal function](): CiviCRM_For_WordPress-&gt;invoke(Object(WP))
  #12 /var/www/html/wp-includes/plugin.php(601): call_user_func_array((Array:2), (Array:1))
  #13 /var/www/html/wp-includes/class-wp.php(737): do_action_ref_array("wp", (Array:1))
  #14 /var/www/html/wp-includes/functions.php(952): WP-&gt;main("")
  #15 /var/www/html/wp-blog-header.php(16): wp()
  #16 /var/www/html/index.php(17): require("/var/www/html/wp-blog-header.php")
  #17 {main}
  </code></pre>
  
  <p>Environment:</p>
  
  <pre><code>.htaccess ssl redirect
  RewriteCond %{HTTPS} off
  RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
  
  CiviCRM Force SSL true
  
  civicrm.settings.php
  define( 'CIVICRM_UF_BASEURL'      , 'https://www.domain.com/' );
  
  Wordpress settings
  WordPress Address (URL) https://www.domain.com
  
  Site Address (URL) https://www.domain.com
  
  PHP 5.6.19
  CiviCRM 4.7.9
  Wordpress 4.5.3
  Eway Single Currency
  w3 Total Cache Version 0.9.4.1
  </code></pre>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2017-09-26T08:29:13.247Z
Comments.Text: This is a very old question, but I have seen the same message with event booking. I'm running CivicRM 4.7.22 on WordPress 4.8.2. I also have WordPress Profile Sync 0.2.6 which I think is also relevant. The problem occurs for the first event booked for a user who has created an account (usually by taking out a membership) where they have used an email address with capital letters in it. On registration the CiviCRM email is made lower case, but not the WordPress email. On event registration you get the problem if they are not logged in and use upper case in the email. The problem doesn't occur i
Comments.UserDisplayName: Mick Kahn
Tags: <registration><cookies>
Title: This page requires cookies to be enabled
ThreadText: # This page requires cookies to be enabled
  
  (Asked by: username_0 on 2016-08-14)
  
  Event registration issues, reports from users make it seem to be with some regularity.
  Message mentions cookies but I am having trouble tracking this down, does anyone have any pointers about where to look?
  CiviCRM log has following:
      Aug 13 19:48:17  [info] $Fatal Error Details = Array
  (
      [message] => We can't load the requested web page. This page requires cookies to be enabled in your browser settings. Please check this setting and enable cookies (if they are not enabled). Then try again. If this error persists, contact the site administrator for assistance.<br /><br />Site Administrators: This error may indicate that users are accessing this page using a domain or URL other than the configured Base URL. EXAMPLE: Base URL is http://example.org, but some users are accessing the page via http://www.example.org or a domain alias like http://myotherexample.org.<br /><br />Error type: Could not find a valid session key.
      [code] => 
  )
  
  
  Aug 13 19:48:17  [info] $backTrace = #0 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Error.php(371): CRM_Core_Error::backtrace("backTrace", TRUE)
  #1 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Controller.php(833): CRM_Core_Error::fatal("We can't load the requested web page. This page requires cookies to be enable...")
  #2 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Controller.php(853): CRM_Core_Controller->invalidKeyCommon()
  #3 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Event/Controller/Registration.php(66): CRM_Core_Controller->invalidKeyRedirect()
  #4 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Controller.php(312): CRM_Event_Controller_Registration->invalidKey()
  #5 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Controller.php(204): CRM_Core_Controller->key("CRM_Event_Controller_Registration", TRUE, FALSE)
  #6 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Event/Controller/Registration.php(45): CRM_Core_Controller->__construct("Event Registration", "null")
  #7 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(307): CRM_Event_Controller_Registration->__construct("Event Registration", TRUE, "null", NULL, "false")
  #8 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(86): CRM_Core_Invoke::runItem((Array:15))
  #9 /var/www/html/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(54): CRM_Core_Invoke::_invoke((Array:3))
  #10 /var/www/html/wp-content/plugins/civicrm/civicrm.php(1227): CRM_Core_Invoke::invoke((Array:3))
  #11 [internal function](): CiviCRM_For_WordPress->invoke(Object(WP))
  #12 /var/www/html/wp-includes/plugin.php(601): call_user_func_array((Array:2), (Array:1))
  #13 /var/www/html/wp-includes/class-wp.php(737): do_action_ref_array("wp", (Array:1))
  #14 /var/www/html/wp-includes/functions.php(952): WP->main("")
  #15 /var/www/html/wp-blog-header.php(16): wp()
  #16 /var/www/html/index.php(17): require("/var/www/html/wp-blog-header.php")
  #17 {main}
  
  Environment:
  .htaccess ssl redirect
  RewriteCond %{HTTPS} off
  RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
  
  CiviCRM Force SSL true
  
  civicrm.settings.php
  define( 'CIVICRM_UF_BASEURL'      , 'https://www.domain.com/' );
  
  Wordpress settings
  WordPress Address (URL) https://www.domain.com
  
  Site Address (URL) https://www.domain.com
  
  PHP 5.6.19
  CiviCRM 4.7.9
  Wordpress 4.5.3
  Eway Single Currency
  w3 Total Cache Version 0.9.4.1
  
  **Tags:** registration, cookies
  
  > **Comments:**
  > **username_1**: This is a very old question, but I have seen the same message with event booking. I'm running CivicRM 4.7.22 on WordPress 4.8.2. I also have WordPress Profile Sync 0.2.6 which I think is also relevant. The problem occurs for the first event booked for a user who has created an account (usually by taking out a membership) where they have used an email address with capital letters in it. On registration the CiviCRM email is made lower case, but not the WordPress email. On event registration you get the problem if they are not logged in and use upper case in the email. The problem doesn't occur i  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_2 on 2016-08-14. Score: 1
  
  Suspect this issue is happening when the site is accessed via `https://example.com` instead of `https://www.example.com`, or when moving from one domain to another midway through a form submission.
  
  See also [this similar SE question](https://civicrm.stackexchange.com/questions/12323/how-do-i-debug-could-not-find-valid-value-for-ct-error-message). This text is in the error message you've pasted:
  
  > Site Administrators: This error may indicate that users are accessing this page using a domain or URL other than the configured Base URL. EXAMPLE: Base URL is <http://example.org>, but some users are accessing the page via <http://www.example.org> or a domain alias like <http://myotherexample.org>
  
  Make sure both WordPress and CiviCRM have a matching URL configured - CiviCRM in `civicrm.settings.php`, WordPress in Settings ⇒ General admin page (ref [WP Codex: Changing the Site URL](https://codex.wordpress.org/Changing_The_Site_URL)). Ideally, make sure that anyone landing on alternate URLs is redirected immediately to the canonical hostname and protocol.
  
  The `.htaccess` snippet in this question addresses consistent protocol but not hostname.
  
  > **Comments:**
  > **username_3**: Might the trailing slash in the URL ('https://www.domain.com/') of civicrm.settings.php cause the problem, which is not present in the wordpress settings ('https://www.domain.com')?  
  
  ---
  
  