The Desktop is just a folder. After you get it's name, you can use anything to copy file. Example below uses WSH.

oShell = CreateObject("WScript.Shell")
lcDesktopFolder = oShell.SpecialFolders("Desktop")
oFso = CreateObject("Scripting.FileSystemObject")
lcFile = FULLPATH("test.txt")
oFSO.CopyFile(lcFile, ADDBS(lcDesktopFolder), .T.)

Check also How do I get the path of special folders from Windows FAQ #16022 and How do I retrieve special folders without relying on Shell.Application? FAQ #16115.

>How do I programatically copy a file (.txt) to the desktop?