java.lang.NullPointerException on version upgrade

Question

My application throws an exception when I install the apk on an existing version.

These are the steps to reproduce my error:

1. Install application (i.e. v1) and run it (no error found)
2. Install the same apk or a new one (i.e. v2) with a minor update
3. A NullReferenceException is thrown
4. Install the same apk of #2
5. Everything works fine

This is the exception:

java.lang.RuntimeException: Unable to start activity
ComponentInfo{com.empystudio.cashflow/com.empystudio.cashflow.MainActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
at android.app.ActivityThread.access$600(ActivityThread.java:130)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4745)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.empystudio.cashflow.MainActivity.onCreate(MainActivity.java:66)
at android.app.Activity.performCreate(Activity.java:5008)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
... 11 more

This is the code of MainActivity

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);

    documentsView = (ImageView) findViewById(R.id.documents_view);
    backupView = (ImageView) findViewById(R.id.backup_view);
    restoreView = (ImageView) findViewById(R.id.restore_view);
    helpView = (ImageView) findViewById(R.id.help_view);
    versionView = (TextView) findViewById(R.id.ver_name);
    ...

Line no. 66 is

documentsView = (ImageView) findViewById(R.id.documents_view);

I tried to comment so many part of my application without success and now I have no idea on how to solve this problem.

[Edit]

Some more info:

1. MainActivity is the launcher Activity in the Android manifest
2. I can't catch the exception (the only stack that I have the one from the Google Play Exception management)
3. If I comment line 66 I still have an exception

[Edit]

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/main_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >

<LinearLayout
    android:id="@+id/adLayout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />

<TableLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_gravity="center_vertical"
    android:gravity="center_vertical"
    android:shrinkColumns="*"
    android:stretchColumns="*" >

    <TableRow
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp" >

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:orientation="vertical"
            tools:ignore="UseCompoundDrawables" >

            <ImageView
                android:id="@+id/documents_view"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:adjustViewBounds="false"
                android:contentDescription="@string/title_activity_documents"
                android:gravity="center"
                android:src="@drawable/menu_documents" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:gravity="center"
                android:text="@string/title_activity_documents" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:orientation="vertical"
            tools:ignore="UseCompoundDrawables" >

            <ImageView
                android:id="@+id/help_view"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:contentDescription="@string/menu_help"
                android:gravity="center"
                android:src="@drawable/menu_help" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:gravity="center"
                android:text="@string/menu_help" />
        </LinearLayout>
    </TableRow>

    <TableRow
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp" >

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:orientation="vertical"
            tools:ignore="UseCompoundDrawables" >

            <ImageView
                android:id="@+id/backup_view"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:contentDescription="@string/menu_backup_database"
                android:gravity="center"
                android:src="@drawable/menu_backup" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:gravity="center"
                android:text="@string/menu_backup_database" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:orientation="vertical"
            tools:ignore="UseCompoundDrawables" >

            <ImageView
                android:id="@+id/restore_view"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:contentDescription="@string/menu_restore_database"
                android:gravity="center"
                android:src="@drawable/menu_restore" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:gravity="center"
                android:text="@string/menu_restore_database" />
        </LinearLayout>
    </TableRow>
</TableLayout>

<TextView
    android:id="@+id/ver_name"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_gravity="bottom"
    android:gravity="right"
    android:textAppearance="?android:attr/textAppearanceSmall" />

[Edit]

Here there are two different APK to reproduce the error:

http://www.empystudio.com/downloads/private/cashflow_1.0.64.apk

http://www.empystudio.com/downloads/private/cashflow_1.0.65.apk

To reproduce the error:

1. Install ver. 64
2. Open it
3. Install ver. 65
4. Open it (here I receive an error)
5. Install ver. 65 again
6. Everything works fine