I purchased turbotax deluxe (ITEM# 1280542) at Costco. How can I return it? I already filed my tax refund 2018 at Turbotax on line. Costco does not accept to refund it.

My old computer (MAC) can not upgrade beyond os 10.10, while Turbotax required MAC os 10.12 or later. So I have to use On-line Turbotax to file my tax 2018.

Unfortunately, Costco does not take return it so I am writing this letter to find out the way that I can refund Costco Turbotax CD. 

I have been using Turbotax last 6 years, and I won't need to buy Turbotax CD from Costco anymore, since On-line process was easier.