OK, that makes things clear. The IRS get really upset if you try to file the same original return twice.
Fortunately, you are able to correct the issue by amending the return.
If you used TurboTax Online, simply log in to your account and select “Amend a return that was filed and accepted.” If you used our CD/download product, sign back into your return and select “Amend a filed return.”
Tips
• You must file a separate Form 1040-X for each tax return you are amending.
Heads up
• Amended returns can take more than three months for the IRS to process.
During the amending process TurboTax will prompt you to input the missing information, i.e. the W-2. If it already appears during the amending dialogues because you entered it already, do not enter it a second time.
And don't forget to amend the state return as well. If TurboTax asks for a payment for the state, do call customer service and ask them to waive it because their instructions were ambiguous and led you astray.
Good news is that you can and will electronically file the amended return. If you print and mail paper forms it could be months before it gets processed.
Finally, it is possible that the result will be that you owe some money because the new refund is smaller than the old one. This can happen if you worked two jobs over the same time period. If so, do pay the IRS by April 18th to avoid underpayment fees.
