You have 3 options for thanking donors.
1) Automated Reply to Donors:
In your account go to “My Menu Options “ and click “Create thank You Message to donors “ . This is automatically sent to donors following each donation.
2) Send message to all past donors:
In your dashboard, click "Edit Existing Pages", Under your your fundraising page , one of the buttons (shown below) is Thank Donors . Follow instructions on this page to send a thank you message.
3) Thank each donor Individually:
Similar to option number 2 above, click "My Donors" and you will see a list of all your donors.
With each donation detail, there is an option to send a Reply to donor.
(Note** this response message also shows on your public fundraising page.)