I note that on 3/8/2025 I received the same TurboTax error message involving a single W-2 for the state of Illinois (no income from any other state) when the total withholding exceeded 20% of gross wages. It is unclear whether this is an actual rule for the state of Illinois or a bug in the TurboTax desktop software. If Illinois cannot accept such a return via e-file, that means tedious paper filing. Moreover, if TurboTax cannot process e-filing for an Illinois return after payment of the filing fee, the user is then required to go through a TurboTax refund request procedure.
