title: No valid settings file could be found
body: <p>I've just installed QT Creator and I wanted to continue developing an old C++ UI application that I designed in 2015. The installation completed without any errors. But when I try to open project and browse to my .pro to load the project, I a pop-up info box appears with the following message:</p>
  <blockquote>
  <p>No valid settings file could be found.</p>
  <p>All settings files found in
  directory &quot;/Users/.../workspace/appname/appname.pro.user&quot; were
  unsuitable for the current version of Qt Creator.</p>
  </blockquote>
  <p>what is the problem and how can I troubleshoot and fix it ?</p>