Here’s the solution!
- Launch System Preferences, either from the dock or from the Apple menu.
- Once the System Preferences window opens, select the General preference pane.
- The middle section of the General preference pane controls when scroll bars appear and a few additional scroll bar options.
- To return the scroll bars to their pre-Lion functionality, select “Always” from the Show Scroll Bars options. The scroll bars will now always be visible, even when you’re not scrolling.