Mac OS: "Can‘t Open Preferences File" Message

Symptom

When a control panel is opened, an alert box with this message appears:

"Can't open the 'control panels name' preferences file."

Solution

The preferences file can sometimes become unusable, resulting in unpredictable behaviors. This is easily fixed by following these steps:

1. Open the System Folder.

2. Open the Preferences Folder.

3. Drag the preference file in question to the Trash.

4. Choose Empty Trash from the Special menu.

5. Restart the computer. The control panel reverts to its default settings.

6. Open the control panel.

7. Reset the desired preferences to match what they were before.

Tip

You can save a good copy of a preferences file to avoid recreating custom settings if this symptom happens again:

1. Make a duplicate of the preferences file immediately after it is installed and set up for the first time.

2. Put the file in a safe place.

If you have to delete the preferences file again, you can simply replace it with a duplicate of the saved, clean file. This preserves your desired preference settings, and reduces any unwanted behavior that may have been caused by a unusable Preferences file.