Can I access previously filed tax return via a different software?

[Yenalga]

Hello,

We want to amend (into married filling jointly) my husband's already filed tax return, which was filed as married separately by mistake to which he has already gotten refunded. My question is, he filed via different application (EZtaxreturn) 

1. Do we need to use the system/application with which he filed before (EZtax)? Or can we access his previous file via a differnt app like Turbotax?
2. Is there a different form to be filled in for amending existing one? If so, please explain to me the steps.  Thank you so much!

[DawnC]

In order to amend the return in TurboTax, you would need to recreate his MFS return exactly as he filed it with the other software, so it may be easier to amend it there.   You need to complete Form 1040X in order to amend it.    IRS info is below.

Current Revision

Form 1040-X PDF

Instructions for Form 1040-X  (Print Version  PDF)