You must have loyalty enable for this to work. The steps to create the export files are as follows:
1. Go to Reports->Exports->Loyalty Program Vouchers
2. You will see the following screen which shows previously created vouchers. You should then press the Create Loyalty Program Voucher Export
3. Choose a name for this voucher issuance and set the date range that the voucher will be valid then press Create
4. You will now receive 2 files. The first file is a list of customers with name and address who will receive vouchers. The 2nd file is of customer with no addresses that need to be updated before they can receive vouchers.
5. Now you can take your voucher list and upload to click2mail.com or other similar system to mail out postcards to your customer with their voucher coupon number. The customer should then bring that postcard back to the store to redeem.
6. To create a barcode from the voucher see this post.
