Is this possible?

Visitor comes to website and signs up for our mailing list.
A coupon code is generated and sent back to them in their "thank you" email
That same coupon code is set up in vsadmin (20% off, one-time use)

We tried giving a generic coupon code, but it gets used multiple times by the same person and shared on sites like Retail Me Not, Coupon Cabin and The Penny Hoarder

We currently use Constant Contact for the mailing list, but if we need to have them sign up for emails through ECT and send out their thank you email there, we can do that and then just import their emails into Constant Contact manually.

Hi Joey, there isn't a feature to auto generate coupon codes as such. But you maybe interested in this add-on that will auto generate coupon after an order is placed to be used on the next order http://www.dlss.ca/proddetail.asp?prod=AutoCoupon

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