OK, I think I've found it. (I didn't originally create this so wasn't aware until I started to RECREATE it...) This payroll run is for some 1099 employees (that they do through payroll for some reason) and it looks like pre-2015 you could do an import and say Yes to Manual Taxes and then not import any taxes and it would work with everyone having 0 taxes. But in 2015, if you have manual taxes set to Yes, looks like you darned well had better have a tax import then or the file doesn't get created. Interesting. So now I think we should probably just change all of the employees to have an override of 0 instead of manual taxes no, but I'll talk to the client about it tomorrow.