[Q] Noob - accidentally removed DownloadProvider.apk

Hello all,
I'm a complete noob in Android and programing, and accidentaly deleted DownloadProvider.apk (using root unninstaller), and trying to remove another app that came installed in my Samsung Galaxy Y Pro Duos...

Can anybody help me with a solution that doesn't need programing and/or advanced knowledge of Android? All works fine, except I cant install any apps, from Google Play or other source...

Help needed really really bad...

Thanks to you all