If you filed it on paper, you don't have to fix the rejection. You will wait until the IRS accepts your paper filing. If you are expecting a refund, you'll know once you receive your refund or can track your return in Where's My Refund? If you owed and made a payment, you'll know once the check is cashed. If you owed and did not make a payment, you'll know when the IRS sends you a bill.