\\servername\sharename\ <this is a location on your network where you copy the file that you want copied to your users' desktop. This isn't the share that you are pointing them to with the shortcut.
let's say that you want to copy a shortcut to your users' desktops that's called AccountingDepartment, where AccountingDepartment is the name of a share on your network. Your script would read as follows...
Const OverwriteExisting = TRUE
Set objFSO = CreateObject("Scripting.FileSystemObject")
objFSO.CopyFile "\\servername\sharename\AccountingDepartment.lnk" , "C:\Documents and Settings\All Users\Desktop\", OverwriteExisting
AccountingDepartment.lnk is the shortcut file that will get copied to everyone's desktop. hope that helps