If you go back through the Final Reviews, TurboTax should tell you if your return contains a form that can't be Efiled. Some state forms are not ready yet, but the program should tell you which ones those are in the review sections.
If you using TurboTax Online, try closing TurboTax, clearing your Cache and Cookies and return to the File section.
If you're still having issues trying to Efile your State, you could try deleting your state, and re-creating it by stepping through the State Interview again.
Here's How to Delete a State Return.