Answers.Body: <p>You'll get that error (regardless of OS) if the <code>SECURITY_KEY</code> variable isn't set in your <code>.env</code> file: <a href="https://github.com/craftcms/craft/blob/master/.env.example#L5" rel="nofollow noreferrer">https://github.com/craftcms/craft/blob/master/.env.example#L5</a></p>
  
  <p>See this step in the install docs: <a href="https://docs.craftcms.com/v3/installation.html#step-3-set-a-security-key" rel="nofollow noreferrer">https://docs.craftcms.com/v3/installation.html#step-3-set-a-security-key</a></p>
  
  <p>If you run the <code>craft setup</code> terminal command, it will generate that key for you, but depending on how you install Craft, you can also manually set it.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-09-16T21:19:45.753Z
Answers.LastActivityDate: 2018-09-16T21:19:45.753Z
Answers.UserDisplayName: Brad Bell
Body: <p>I was tried to run Craft 3 on a Windows machine, it has shown the multiple errors.</p>
  
  <pre><code>An Error occurred while handling another error:
  yii\base\InvalidConfigException: craft\web\Request::cookieValidationKey must be configured with a secret key. in D:\xampp\htdocs\craft\vendor\yiisoft\yii2\web\Request.php:1554
  Stack trace:
  #0 D:\xampp\htdocs\craft\vendor\yiisoft\yii2\web\Request.php(1536): yii\web\Request-&gt;loadCookies()
  </code></pre>
  
Tags: <craft3>
Title: Craft CMS 3 error in Windows installation process
ThreadText: # Craft CMS 3 error in Windows installation process
  
  (Asked by: username_0 on 2018-09-16)
  
  I was tried to run Craft 3 on a Windows machine, it has shown the multiple errors.
  
  ```
  An Error occurred while handling another error:
  yii\base\InvalidConfigException: craft\web\Request::cookieValidationKey must be configured with a secret key. in D:\xampp\htdocs\craft\vendor\yiisoft\yii2\web\Request.php:1554
  Stack trace:
  #0 D:\xampp\htdocs\craft\vendor\yiisoft\yii2\web\Request.php(1536): yii\web\Request->loadCookies()
  
  ```
  
  **Tags:** craft3
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2018-09-16. Score: 1 | Accepted answer
  
  You'll get that error (regardless of OS) if the `SECURITY_KEY` variable isn't set in your `.env` file: <https://github.com/craftcms/craft/blob/master/.env.example#L5>
  
  See this step in the install docs: <https://docs.craftcms.com/v3/installation.html#step-3-set-a-security-key>
  
  If you run the `craft setup` terminal command, it will generate that key for you, but depending on how you install Craft, you can also manually set it.
  
  
  ---
  
  