I found that if I turn on the Production Manager, then open Flexi - do my stuff, send to cut/plot to manager when cutter is offline, go online at control panel and then send, I have no problems and can send a number of files or repeat files using the USB. If I don't follow this order of Manager, Flexi, manager, cutter the communications are unreliable between the programmes and the cutter. I am very new to my plotter but managed to set up XP, manager and Flexi with no issues at all using the USB. As a Mac user this was all new to me. If only I was as confident with the Vinyl cutter hardware.