I had try to factory reset. And nothing happen at all. Still cant download something such a whatsapp. I want to download anything else, it keep repeating "there was a problem parsing the package"
Welcome to Android Central! Which device? Is this only for app installations? Are you installing from Google Play Store?
Try going to Settings>Apps>All, select Google Play Store, and Clear Cache/Clear Data, then Force Stop. Do the same for Download Manager. Now try again.