For several years, I have noticed a data flow problem between the Federal module and Missouri state module (desktop) that I have addressed with overrides or manual entries to Missouri form MO-A. I'm sending this note in the hope that the underlying issue will finally be fixed.
When a Federal Form 1099-DIV or -INT form includes interest/dividends on federal obligations, the amount is flowing to the Missouri model but is double-counted on line 8a of form MO-A (i.e., $42 on the -DIV or -INT form is reported as $84 on MO-A). I currently fix this with a manual override.
Likewise, when a Federal Form 1099-DIV or -INT form includes interest from states other than Missouri (and the multi-state "XX" code is recorded on the 1099-DIV or -INT form) the amount is not flowing at all to line 1a of form MO-A. I currently fix this with a manual data entry.
You should view this thread, especially the portions that are posted at the bottom in the last week.
Just today I was notified through Inuit's "Office of the President" that the case was sent to the development team.
I have submitted a multipage document to them to try to get them to address this error.
For your information, I was told if I manually override the values on Mo Form A line 8a that TurboTax would not guarantee the return. The irony.
As you are obviously aware, the error in their processing has been present for three years.
I also have discovered what order to enter the dividends in so that the error does not raise its ugly head, at least on a single state return.