Error 492 is a specific error of the PlayStore. We cannot fix it for you since it is not an error on our side. But the good news is that you will be able to fix it yourself by following the steps below:
1. Clear Cache of Google Play: This is a common fix and have worked for most users. Go to settings and open your apps list. Then tap on "Google Play Store" and select "Clear Data". Repeat the same steps to clear data for "Google Service Framework". Now open Google Play and download/update your app(or game).
2. Clear dalvik cache: If you are a custom ROM user then you can follow this method. Simply reboot into recovery and then go to advanced >> select "wipe dalvik cache". Then reboot system, open Google Play Store and then download the app.
3. If you have installed your app on a corrupted SDcard, that can also cause this error. Take out the SDCard and check it for errors. Then uninstall the app and re-install it in your device. Re-insert the error free SDcard and then move apps to SD card.