That can happen. I have two sets of USB ports on my computer and the i1 pro only works on one of them. I attribute this to the problem you describe. It is device dependent as the USB ports that it does not work on seem fine for other devices (including ColorMunki). Alan From: argyllcms-bounce@xxxxxxxxxxxxx [mailto:argyllcms-bounce@xxxxxxxxxxxxx] On Behalf Of M. Kupiec Sent: Friday, July 15, 2011 7:51 AM To: argyllcms@xxxxxxxxxxxxx Subject: [argyllcms] Re: Strip read failed due to communication problem (i1pro W7x64) I'm wondering if the problem is not in not enough usb power while measuring. I've made some measurements and there in 4,95V in pc and 5,10V in working laptop Seems normal but thats idle voltages At evening im gona to try with powered USB hub, and additional usb pci card. Pozdrawiam Marcin