点击应用，就报App isn't installed解决方法

点击应用，就报App isn't installed
点击应用，就报App isn't installed
看后台Logcat报：
06-14 21:04:14.995: E/Launcher(539): Launcher does not have the permission to launch Intent
本人新手，不知道是什么问题导致的。AndroidManifest.xml如下：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.zbiti.epayCheckApprove.activity"
    android:versionCode="3"
    android:versionName="1.2" >

    <uses-sdk
        android:minSdkVersion="11"
        android:targetSdkVersion="19" />

    <uses-permission android:name="android.permission.RESTART_PACKAGES" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="android.permission.READ_PHONE_STATE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <!-- 当前的Android程序就支持了多种分辨率 -->
    <supports-screens
        android:anyDensity="true"
        android:largeScreens="true"
        android:normalScreens="true"
        android:resizeable="true"
        android:smallScreens="true" />

    <instrumentation
        android:name="android.test.InstrumentationTestRunner"
        android:label="Tests for My App"
        android:targetPackage="com.zbiti.epayCheckApprove.activity" />

    <application
        android:allowBackup="true"
        android:hardwareAccelerated="false"
        android:icon="@drawable/title"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <uses-library android:name="android.test.runner" />

        <activity
            android:name="com.zbiti.epayCheckApprove.activity.LoginActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.MyBacklogActivity"
            android:launchMode="singleTop"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.MyBacklogTypeActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.BzdActivity"
            android:parentActivityName="android.app.TabActivity"
            android:screenOrientation="portrait" >
            <meta-data
                android:name="android.support.PARENT_ACTIVITY"
                android:value="android.app.TabActivity" />
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.WelcomeActivity"
            android:screenOrientation="portrait" 
            android:exported="false">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.MyWorkActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.MyCheckListActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.SelectActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.SelectProcessUserActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.SettingActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.UpdataPassActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.MyApplyListActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.MyTrustActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.AddTrustActivity"
            android:screenOrientation="portrait" >
        </activity>
        <activity
            android:name="com.zbiti.epayCheckApprove.activity.SelectTrustPersonActivity"
            android:label="@string/title_activity_select_trust_person" >
        </activity>
    </application>

</manifest>

------解决思路----------------------
把WelcomeActivity的android:exported="false"这句删掉。