t took me a while to find this one and solve it. I had tried the optional state sales tax and entered the state sales tax rate on one line and the local sales tax rate on another. Both had entries for 1/1/2016 to 12/31/2016 so the total was more than 366 (732 days!) The solution was to go back in the options and total the all the rates into one total rate and delete the other sales tax entry. Smart check passes, no more problem.
I'm having this problem now but can't figure out how to go back and change it
@Causbyma If you are working on your 2020 return, and lived in the same state all year, try entering 01/01/2020 and 12/31/2020 as dates 'lived in this state'.
If you moved out of that state in 2020, enter 01/01/2020 and the date in 2020 that you moved out of that state.
If you get a '366 days' error, try using 01/02/2020.
Click this link for instructions on Entering Sales Tax.
Remember that Sales Tax is an Itemized Deduction, so you won't see it if you use the Standard Deduction.
Click this link for info on Claiming Sales Tax.
I ran into this issue as well and it turns out I had accidentally added a sales tax line item for a vehicle we purchased in 2020 twice. I'm not sure how that happened but went back into Deductions and found the Sales Tax area & deleted the duplicate. It then let me move forward and file.