Thiagu, go here: http://www.worldcommunitygrid.org/ms/device/viewDevices.do and select the profile for the machine that has the problem. As Scribe suggested, you probably have "Do work while computer is in use?" set to No. Change that to Yes and it will do work even while you use your computer. It will still run at lowest priority, so it won't interfere with other things you're doing on your computer.