[TGabriele]

That's the HTC Task Manager you're looking for. I'm not sure if Sprite Restore is deleting the pertinent files on you or not, but if its not, the following steps will help you get it back. Tap the Start menu, tap Settings, tap System, swipe down to Task Manager and tap on it (hopefully its still there!). Tap on the "Button" tab on the bottom and make sure that the "Enable Quick Menu on Today screen" checkbox is checked.

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