Why is my service code from Costo not working

[SuziM]

Are you using TurboTax Desktop? Your license code is a 16-character combination of letters and numbers (XXXX-XXXX-XXXX-XXXX) that verifies the software, lets you to finish installing, and begin using TurboTax Desktop.

Here’s where to find it:

If you purchased TurboTax Desktop from an authorized retailer, your license code is printed on the front of the box insert.