[android help] Preference cannot cast java.lang.boolean to String

I have the following Preference class:

public class AppPreferencesActivity extends PreferenceActivity {
    private SharedPreferences appPrefs;
    private SharedPreferences.Editor prefEditor;
    private Mediator mediator;
    private SharedPreferences.OnSharedPreferenceChangeListener listener;
    private User user;
    @SuppressWarnings("deprecation")
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //---load the preferences from an XML file---
        addPreferencesFromResource(R.xml.preferences);
        this.appPrefs = PreferenceManager.getDefaultSharedPreferences(this);
        this.mediator = (Mediator) getApplication();    
        this.prefEditor = appPrefs.edit();
        this.user = mediator.getUser();
        setPreferences();
        listener = new SharedPreferences.OnSharedPreferenceChangeListener() {
            public void onSharedPreferenceChanged(SharedPreferences prefs, String key) {
                // Implementation
                updatePreference(key);
                Toast.makeText(AppPreferencesActivity.this,
                        "Information updated",
                        Toast.LENGTH_SHORT).show();
            }
        };
        appPrefs.registerOnSharedPreferenceChangeListener(listener);

    } 
    private void setPreferences(){
        prefEditor.putString("nameEdit", user.getName() + " "+user.getLastName());
        prefEditor.putString("streetEdit", user.getStreetName());
        prefEditor.putString("streetNumberEdit", ""+user.getStreetNr());
        prefEditor.putString("emailEdit", user.getEmail());
        prefEditor.commit();
        preferenceAddSummary();
    }
    public boolean checkEmailStatus(){
        return appPrefs.contains("emailEdit");
    }
    @SuppressWarnings("deprecation")
    private void preferenceAddSummary() {
        for (Entry key : appPrefs.getAll().entrySet()) {
            findPreference(key.getKey()).setSummary(appPrefs.getString(key.getKey(), "Not yet entered")); 
// this is where im getting the error

            }

However when i run this i get the following

Cannot cast Java.lang.boolean to Java.lang.String

I get this error at the loop im calling to setSumary can anyone tell me why this is happening?

UPDATE

Here is a print of my stacktrace:

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stackoverflow.comm