then try this.
Create a shortcut of that file, eg to the Desktop. Right click the Start Menu button and choose an "Explore", either Explore or "Explore all users". Navigate to the Accessories folder and see if there is already a shortcut there for Windows Explorer. if not, drag the shortcut you created on your Desktop to this folder.
See if that works.
Why did it disappear? Not sure as I haven't seen that before, not when Explorer still works.
Mark

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