I finally had 1 helpful rep (after about 10 wrong answers). His advice worked for me.
Just delete the entire 1099 upload. Then enter in the summary values (Short-Term Box A' and B, Long-term Box A's and B's and the Unknowns). Once you're done it will correct the error and you should be able to file. I was told to mail in form 8453 as a supplement to your efile but the irs processed my return without it.
For some reason if you don't enter the summaries the software starts entering incorrect values on Part I, Line 1b of the Schedule D. By just entering the totals it applies the correct deduction (if you're eligible) in Part II, Line 21 and the appropriate values in Part I, Lines 1b and 2.
