I need to amend previous year return (2013). I have the 2013 software and files on my computer and 2017 software. What do I use?

[DoninGA]

Only the TurboTax software for tax year 2013 can be used to amend a 2013 tax return.  An amended tax return can only be printed and mailed, it cannot be e-filed.  Also, if you are filing the amended return for a tax refund, the time to file has expired.  The 2013 amended return had to be filed on or before April 18, 2017 or if an extended 2013 return on or before October 16, 2017. 

Note that TurboTax no longer supports tax year 2013.