"quick transfer"

I've been using the basic functions of Smart FTP for a while. Recently (for reasons I'm unsure of) a function/button was being displayed between my to vertically tiled remote & local windows (I assumed it was some "quick transfer" thing-a-me-bob). But now it is not there, and i am unable to activate it???? If it is "quick transfer" I can see this option displayed in view/toolbars/ but am unable to "check". If it is not "quick transfer", can some one advise me how to activate this device.