When paper-filing IRS Form 1040X Amended U.S. Individual Income Tax Return, it is important to attach any forms or schedules used to figure the revised tax.
As it is not possible for the program to know which forms or schedules those may be, it is up to the taxpayer to print and send them with the amendment.
In the amendment section of the Q&A, on the screen titled Amended Return - Mail Form 1040X, the first paragraph states "Mail Form 1040X and any accompanying documents to the Internal Revenue Service Center for the place where you live."
To view this screen in your TaxAct® return: