*New* Why won't this Animation stop?

You define a new local variable called example inside the if part. This means that the variable example does not exist outside of the if then... part.

The best way to fix this is to define example right at the start:

Enabled = false
local example = Humanoid:LoadAnimation(script.Parent.Animation)
script.Parent.MouseButton1Click:connect(function()
    if Enabled == false then
        Enabled = true
    local Humanoid = game.Players.LocalPlayer.Character:WaitForChild("Humanoid")
    example:Play()
    else
        if Enabled == true then
            Enabled = false
        example:Stop()
    end
    end
    end)

Another way to fix this is to remove the "local" before the example like this:

example = Humanoid:LoadAnimation(script.Parent.Animation)

or you could just redefine example (but this isn't a very good way of doing things)

example:Play()
    else
    local example = Humanoid:LoadAnimation(script.Parent.Animation)
        if Enabled == true then
            Enabled = false
        example:Stop()
    end
    end
    end)