How to stop sharing a folder?

Windows Help says "To stop sharing a folder by using the Windows interface:

Open Computer Management. In the console tree, click System Tools, then click Shared Folders, and then click Shares. In the details pane, right-click a shared folder, and then click Stop Sharing."

I've done exactly that. When I right-click any shared folder, I get a menu with four choices: Open, All Tasks, Refresh, Help. The only choice under "All Tasks" is "Open". Why don't I see a "Stop Sharing" choice?

Yes, that worked. I assume the help section I referenced must have been out of date. Thanks!