If Sketch Manger is opening the wrong application, you should be able to reset it by following these simple steps: Select “Go To” / “Documents” / “Adobe Scripts” Right click on the script called “pngloader.jsx,” then click “Open with …” and select the correct application Click “always open with” on the bottom of the window, and save this setting
After completing these steps, please re-start Sketch Manager to before ensuring that the correct application is opening.