I updated to PT 2021 64 bit if I click on the shortcut it opens as PT2021, but if I click on a midi file and choose "open with" power trtacks it opens in PT 2020. ( the about powertracks info says this) I looked in control panel under programs and only PT 2021 is listed. Is PT 2020 still somewhere on my computer?

yes - if it's like RB 2021, PT 2021 is 64 bit but you get to keep PT2020 as a 32 bit program

right click on a seq file and change the association to PT 2021 but you might like to use the 32 bit program if you have some 32 bit plugins that don't work with 2021

Thanks for the info.