To Copy a Link or a Folder Using Drag-and-Drop Operation

In the Links tab of the Explorer dialog, select the link or folder to be copied.
Press <Ctrl> and drag the link or folder to the desired location or folder. You can also copy a link or folder from any link set to the active file link set.
By default, the name of the link or folder appears in the Name field, but with a numerical increment (such as Index-1).

A line appears, showing you where the link or folder will be copied when you release the mouse button. If you drag a link or folder to a closed folder, a rectangle appears around the closed folder and the selected link or folder will be copied in it.