You are having problems because for an amended return you can't schedule an automatic payment. You need to select, "I will mail a check" or "Pay online at IRS.gov."
You should be able to e-file, but with amendments, it doesn't always go through, depending on your situation. Try it and see what happens. If it doesn't let you, you will have to print and mail.
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"
