Dear @JeffreyR77 and @Anonymous_
You might read the other filers who have clearly followed the step-by-step instruction as you showed us and told the program that they have elected to be treated as an S-Corp already, but TurboTax Business insisted on having them attach Form 2553 to their main return (Form 1120S). I'm having exactly the same issue and can't get TurtoTax Business to let me go beyond this point without attaching a Form 2553, which I already filed last year when I formed my S-Corp (one has to file within a couple of months or so).
The problem is caused by TurboTax Business mistakenly marking "Yes" on Section G of form 1120S. As @mjolley said, manually change this to "No" got me through this problem.
It's definitely something TurboTax Business is doing wrong and should be fixed.
Regards,
TC
