@JulieS Revisiting this thread as I finished and e-filed my return today.
Although the trick to move Schedule D line 8a to line 8b allows you to progress through the tax return on TurboTax desktop, ultimately TurboTax will not let you e-file the return, because it detects an "error" that requires a date entered in the Capital Asset Sales Worksheet (under Form 1099-B Worksheet) for Box D transactions.
Assigning a code M to Box D transactions, does not work either. TurboTax ignores the code and will still place totals on Schedule D line 8a.
I hope this "restriction" can be addressed by the programming team for future versions of TurboTax, where the user simply wants to enter their 1099-B Box D totals on Schedule D line 8b, instead of line 8a. It is a choice literally stated on the Schedule D form itself: "However, if you choose to report all these transactions on Form 8949, leave this line blank, and go to line 8b."
