To enter personal property (or inherited property that is considered personal property) on Schedule D:
When you are going through the Q&A for Form 1099-B, on the screen titled Investment Sales - Adjustment Code(s), you should select Code L - Other Non-Deductible Loss (including personal loss). When this code is selected, the gain/loss column on the Schedule D will be zero instead of a negative number (as is appropriate since losses on personal property are not deductible). On the following screen, the loss adjustment amount will need to be entered or verified.
To reach that screen in your TaxAct® return:
Note that if the inherited property is not considered to be personal use property then you would not select Adjustment Code L. This will ensure the loss would still carry to the Form 1040.