Follow the steps below to change your default program for a specific file type using the registry editor:

1. Press Windows key + R to open the Run dialog box.
2. Type regedit in the run dialog box and press Enter.
3. Navigate to the following path in the registry editor: HKEY_CLASSES_ROOT\.[extension]
4. In the right-pane, locate the Default string value.
5. Right-click the Default string value and select Modify to open the edit string window.
6. Input the application path you want to use as the default program to open the target file type.
7. Click OK to save the changes.