Your activation code is unique to you and the products you've purchased, and as such, only one code can be active on your account at a given time. The software doesn't allow for a multi-licence experience, so if a licence is already active on your account and you try to enter a new one, you may get an error message.

For further information, please see our TurboTax FAQ: In the online edition of TurboTax, how do I use a prepayment code?

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