Erro parsing XML: not well formed (invalid token)

I checked maximum solutions given in website but still i'm not able to find error and solve this problem. Please help me to solve this problem.

here is my code

<?xml version="1.0" encoding="UTF-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@color/white"
android:orientation="vertical" >

<LinearLayout
    android:xmlns:facebook="http://schemas.android.com/apk/res-auto"
    android:id="@+id/fbuserinfo"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="10dp" >

    <com.facebook.widget.ProfilePictureView
        android:id="@+id/user_profile_pic"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center_horizontal"
        facebook:preset_size="small" />

    <TextView
        android:id="@+id/user_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:text="@string/facebook_loading"
        android:textColor="@color/black"
        android:textSize="18sp" />
</LinearLayout>

</RelativeLayout>