04-12 09:41:33.425: W/PackageInstaller(5015): Parse error when parsing manifest. Discontinuing installation
04-12 09:41:33.425: W/PackageParser(5015): Unable to read AndroidManifest.xml of /mnt/sdcard/Download/downloadfile.apk
04-12 09:41:33.425: W/PackageParser(5015): java.io.FileNotFoundException: AndroidManifest.xml
04-12 09:41:33.425: W/PackageParser(5015): at android.content.res.AssetManager.openXmlAssetNative(Native Method)
04-12 09:41:33.425: W/PackageParser(5015): at android.content.res.AssetManager.openXmlBlockAsset(AssetManager.java:487)
04-12 09:41:33.425: W/PackageParser(5015): at android.content.res.AssetManager.openXmlResourceParser(AssetManager.java:455)
04-12 09:41:33.425: W/PackageParser(5015): at android.content.pm.PackageParser.parsePackage(PackageParser.java:425)
04-12 09:41:33.425: W/PackageParser(5015): at com.android.packageinstaller.PackageUtil.getPackageInfo(PackageUtil.java:74)
04-12 09:41:33.425: W/PackageParser(5015): at com.android.packageinstaller.PackageInstallerActivity.onCreate(PackageInstallerActivity.java:277)
04-12 09:41:33.425: W/PackageParser(5015): at android.app.Activity.performCreate(Activity.java:4465)
04-12 09:41:33.425: W/PackageParser(5015): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
04-12 09:41:33.425: W/PackageParser(5015): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
04-12 09:41:33.425: W/PackageParser(5015): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
04-12 09:41:33.425: W/PackageParser(5015): at android.app.ActivityThread.access$600(ActivityThread.java:123)
04-12 09:41:33.425: W/PackageParser(5015): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
04-12 09:41:33.425: W/PackageParser(5015): at android.os.Handler.dispatchMessage(Handler.java:99)
04-12 09:41:33.425: W/PackageParser(5015): at android.os.Looper.loop(Looper.java:137)
04-12 09:41:33.425: W/PackageParser(5015): at android.app.ActivityThread.main(ActivityThread.java:4424)
04-12 09:41:33.425: W/PackageParser(5015): at java.lang.reflect.Method.invokeNative(Native Method)
04-12 09:41:33.425: W/PackageParser(5015): at java.lang.reflect.Method.invoke(Method.java:511)
04-12 09:41:33.425: W/PackageParser(5015): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
04-12 09:41:33.425: W/PackageParser(5015): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
04-12 09:41:33.425: W/PackageParser(5015): at dalvik.system.NativeStart.main(Native Method)
请问如何解决这个问题。