Thanks for looking into this.I do have entries in box 14 and 15. The form does not contain a box 16 but TurboTax insists it must be entered when I submit the fo...

Regarding:unless there is a different amount showing in Box 2a.What then? Use Box 2a amount for the missing box 16?

I have the same situation, and have for multiple years. It is a regular 1099-R form, and there is no box 16.