The default Pycharm interpreter is

Every time I open Pycharm I get a "Pyhon interpreter configured for the project", so I go to Preferences> Interpreter and select it from the list. But as soon as I close Pycharm and reopen it next time, I get the same message. I have lost my mind trying to find an answer to this question, is there a solution? I have had Piacharm for a long time and have never had such a problem. Fresh installation to win 8.1.