I suggest you to check income forms (W-2, 1099-INT etc) for state withholding, it might be copied to those forms by mistake when you go through smart check.
Finally I found the problem, I searched the same number in Federal return and it was added to one of my 1099-INT when I went through smart check. It doesn't aff...
I spent another whole day with several tech specialists ( transferred to several "higher-up" techs), and even talked to a CPA from Turbo Tax, just got off phone...
Gosh, now I am at the situation that I couldn't e-file my state tax return because of this hidden state tax withholding in your program. I have to edit w-2 form...