====== Uninstalling Gift Certificate ======
To disable the module you must login to your server's terminal, go to Magento install directory and perform:
  php bin/magento module:disable Unirgy_Giftcert

If full removal is needed, then all extension's files should be removed.
Files are located at:

> app/code/Unirgy/Giftcert/

  
If you want to remove all database traces of the module you should:
<code mysql>
DROP TABLE `ugiftcert_cert`;
DROP TABLE `ugiftcert_history`;
DELETE FROM `eav_attribute` WHERE `attribute_code` LIKE '%giftcert%';
DELETE FROM `catalog_product_entity` WHERE `type_id`='ugiftcert';
</code>

Removing databse entries is not required except of <code mysql>DELETE FROM `eav_attribute` WHERE `attribute_code` LIKE '%giftcert%';</code> which will prevent any PHP errors due to missing classes for GC attributes.
If you want you can scan ''sales_flat'' tables for any ''%giftcert%'' columns and remove them.