If you entered the W-2 information on your state tax return before you efiled it, there is no need to send a copy of the W-2 to the state. All the information they need is in the efiled return. The only reason you would need to send a copy of a W-2 is if you printed and mailed your return instead of efiling it. Not sure what happened in prior years.
You cannot attach copies of your forms W-2 to your NY tax return if you e-file.
And when you e-file, you are not required to attach copies of your forms W-2.
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