Prestashop Paypal Module was a bit buggy in upgrading from v.1.4.4.1 to v.1.6.0.9 including some additional modules.
PayPal v.3.7.2 & PayPal USA, Canada.
By default PayPal v.3.7.2. was enabled with correct configuration. However, upon testing the checkout process (edit /config/defines.ini.php to display errors) there where errors.
PrestaShop PayPal Module; PayPal Login User Doesn’t Exist.
[PrestaShopDatabaseException]
Table ‘domain_DBname.ps_paypal_login_user’ doesn’t exist
Steps to resolve..
Step 1.) Uninstall PayPal v.3.7.2 module.
Step 2.) Install PayPal USA, Canada module.
Step 3.) Configure PayPal USA, Canada module.. Module in section ‘PayPal API Settings’, enter your PayPal email you use to log with PayPal.
Test site..
Success!
PayPal, USA, Canada problems: http://www.prestashop.com/forums/topic/295266-paypal-usacanada-problems/