All of a sudden, "Income Tax Slab not set in Salary Structure Assignment"

I’m experimenting with payroll. I’ve run many tests like:
Create several Salary Components,
Create Salary Structure (with submit),
Assign Salary Structure (with submit),
create salary slip (but not submit). Desired output was not realized so I don’t submit it.
Then reverse my steps so I can try another way:
Cancel Salary Structure assignment,
Delete Salary Structure assignment,
Cancel Salary Structure,
Delete Salary Structure,
Modify some Salary Components,
Then start from step one again.

I’ve performed the above routine many times in my trial and error.

Now all of a sudden I’m getting the error “Income Tax Slab not set in Salary Structure Assignment” when trying to create a salary slip.

I don’t have any salary components with "
Is Income Tax Component" checked, so why am I seeing this error?

Do I have to perform a fresh install?

Any idea what to search to see what I may have broken or corrupted?

FYI, my workflow has only included one salary component and one deduction component.
The deduction component has no check boxes selected and is based on the formula “gross_pay * .08”.
The earnings component has no check boxes selected and is based on the formula “base / 52”.