can't associate pdf file to acrobat reader

it's a week i can't open pdf with acrobat reader or any other pdf reader. i've uninstalled and reinstalle many time and different version, but it's the same situation, i can't open pdf file without telling with which software i wanna to open pdf file. now i have only acrobat reader and when i double click to the file (any kind not only one), my pc asks what software i wanna to open, i click on acrobat reader, then acrobat asks me if i wanna choose that software as the default one, then i click on -pdf extension but nothing changed. i don't know what to do next.

Acrobat reader version 11.0.19

os win 8.1 64x

how can i solve?

thank you