After you file
It is possible that the W-2 was transferred over from a previous year and a 2nd W-2 was also entered. You can quickly tell if this happened by searching for w-2 in TurboTax (once you have the return opened) and using the Jump to W-2 link. You will see the W-2 summary which will list all W-2s on your tax return. If you have two from the same employer, with the same amount, you will need to delete one of those W-2 and then ensure the other one is correct and complete. Then you can proceed through the amending process.
Form 1040X is ready to use. When you sign in to TurboTax, you can now select the AMEND option at the bottom of the Tax Home page (under Your tax returns and documents).
