If you have received your Green Dot Personalized Card, you should go to www.MyGreenDot.com/activate or call 1-866-795-7605 to activate your card.
What is Green Dot Personalized Card?
The Green Dot Personalized Card is a prepaid card that you can use anywhere debit MasterCard or Visa cards are accepted worldwide. You don’t need personal credit to apply the card. And you should add money to your Card in order to use it. The Card can be used at ATMs and can also be reloaded (more money can be added to them). Your purchases and ATM withdrawals are debited from your Card balance.
To activate your Personalized Card the primary cardholder must log-in with the Personalized Card number, expiration date and password. Click here to start the activation
Learn more from http://www.mygreendot.com/activate