Plesk is not accessible: PHP Fatal error: Composer detected issues in your platform: Your Composer dependencies require a PHP version ">= 7.4.0".

Symptoms

• Plesk is not accessible with the following error:
  

  CONFIG_TEXT: PHP Fatal error: Composer detected issues in your platform:
  Your Composer dependencies require a PHP version ">= 7.4.0".
  You are running 7.3.27.

• Plesk 18.0.34 or lower is used

Cause

Sectigo upgrade requires PHP 7.4+

CONFIG_TEXT: # grep -Ri ">= 7\.4\.0" /usr/local/psa/admin/plib/modules
/usr/local/psa/admin/plib/modules/sectigo/vendor/composer/platform_check.php: $issues[] = 'Your Composer dependencies require a PHP version ">= 7.4.0". You are running ' . PHP_VERSION . '.';

Plesk bug: #EXTPLESK-4777, which was resolved on Jun 22, 2023.

Resolution

Disable the extension:

1. Connect to the server via SSH / RDP

2. Remove the extension by executing the following command:
   

   # plesk bin extension -u sectigo

3. Install it anew:
   

   # plesk bin extension -i sectigo