I need to amend my 2015 tax return on my Mac. TT already sent me the download to this but I can't upload my 2015 return in order to amend it.

You don't upload the return ... you have to open the .tax2015 file so do you have that file on your computer ?

If so you need to install & update the program then click on the file tab in the menu bar to open/find the .tax2015 file.

Do you mean that you did your 2015 return online and now need to amend.  You do not "upload" the 2015 return, but need to "download" the tax file from the online to your computer.

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