I assume you are talking about box 15 on a W-2. What exactly do you mean by "can't enter"? If you click in the box for the employer's state ID number and type, do the numbers that you are typing not appear in the box on the screen? Or is there something else preventing you from entering the employer's state ID number? If you get an error message, what is the exact message, word for word? For the state there is a drop-down list. Is your state not in the list? What state is it? If you are in a state that does not have state income tax, you do not need to enter it. If there is no state income tax withheld in box 17, you can leave boxes 15 through 20 empty in TurboTax.
