Long carvs

Thanks, I have another question about long carves… I use Picsender and I also have an X-Controller. When I pause, I pause the Picsender first and then the X-controller. I then turn off the spindle. The next day when I return to start the carve where I left off I receive an error and (missing an S on gcode line whatever) have to restart the carve over. My question is there another way to be able to start a long carve where you left off? If so , what am I missing?