To edit the registry, first back it up, then do the following:
- Open your favorite registry editor and navigate to this key: HKEY_CLASSES_ROOT \ SystemFileAssociations \ image \ shell \ edit \ command
- Doubleclick the entry in the right pane.
- In the data value field, type the path to the program you want to use (for example: "c:\Program Files\IrfanView\i_view32.exe" "%1"
You can change the editor for a particular file type this way:
- Click Start Run
- Type CONTROL FOLDERS
- Click the File Types tab.
- Select the file type from the list and click the Advanced button.
- Click New.
- In the Action box, type Edit
- In the Application Used To Perform Action box, type the full path to the application you want to use to edit pictures.
- Click OK twice to close the dialog boxes. This sets the default image editor for the selected file type.