Use the one sale at a time mode of entry.  The small amount of dollars you're reporting on the attached picture means you just don't have very many trades to report and you might have thought that the "summary" entry method would be so much easier with understanding that you have to MAIL IN information after you file.  Both Box 4 and Box 16 - the taxes boxes - are available to you if you enter one sale at a time.

You don't have to MAIL IN for box A or box D.

Thank You!  That might do it. I wonder why the program doesn't tell you that. In fact I initially did the long way, but all the 12 securities were bought and sold in the same year (2017) and the program wouldn't accept that so I went to Summary. I'll have to override, I guess and file a 1040X. Thanks again.

Since you took the Summary election, you won't get the option to enter a 1099-B tax withheld.

Instead list it as an "Estimated Tax Payment" under

Deductions and credits -- Other income taxes.
OR
go back and choose one sale at a time. You can't use Summary election for transactions with adjustments. (Withholding is not an adjustment.)

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