Error: Error Launching activity

Esta constando o erro : Já limpei o cache e fiz todos os passos do Resolvendo possiveis problemas

O código da tela AndroidManifest.xml esta assim:

<application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.Agenda" >
        <activity android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN "/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
    </application>

A classe esta assim:

import android.app.Activity;

public class MainActivity extends Activity {

}