I'm having the same issue. I've actually been having a version of this for months: I've been unable to open Payroll Setup - getting this same error every time. I used to be able to open the features I needed, however, by clicking on "Manage Payment Methods" but now that gets the same error.
I hesitate to speculate but it seems as if Intuit is trying to make it harder and harder for users of Quickbooks Desktop and trying to force the Online product by not maintaining Desktop.
