Installing Drupal

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Hello,

I tried to install Commons Distribution ver 7.x-3.32 and encountered an error which I don't have any clue what it is about. Can anyone explain what has gone wrong or is it a bug in the code?

The error message is shown below:

Hostmonster shared hosting. I have successfully installed Drupal 7 sites under this account before. I am excited to begin with Drupal 8 but cannot continue.

PHP Version 5.6.15
MySQL Version 5.5.42-37.1-log

This is an issue related to the following during installation:

Database support Disabled
Your web server does not appear to support any common PDO database extensions. Check with your hosting provider to see if they support PDO (PHP Data Objects) and offer any databases that Drupal supports.

I have installed several times successfully in two subdirectories, but whenever I attempt to go to another page i get the https://www.modelsushi.com/core/install.php (drupal is already installed page)

I have followed this tutorial drupal 8 multisite
changed permissions Step 3

I've entered the trusted host patterns code in settings.php:

I'm trying to get the coupon module working on drupal 7. Once I set up my discount and once a user adds items to the cart every page gives and error check log.

2015/11/05 23:58:00 [error] 16513#0: *720 FastCGI sent in stderr: "PHP message: PHP Fatal error: Call to undefined function commerce_coupon_type_enable() in /var/www/html/drupal/sites/all/modules/commerce_coupon_pct/commerce_coupon_pct.install on line 57"

So far the only way to fix the error on every page is to disable all coupon and discount modules.