The computer is not communicating with the printer. A cable could have come ajar, or a driver in the computer could have failed. Check your cables to the printer, and make sure it's turned on. Go into your control panel, and printer and make sure you see your printer there. Click on the Samsung and make sure under ports that usb is selected. Also, go into your device and hardware settings, and ensure your usb ports are recognized. If they aren't, update the drivers or reinstall them.
If you don't see your printer there, reinstall your CD that came with it. You may have to try this anyway, if nothing works.
Other than getting the software reinstalled, there may be a problem with the printer, and you might run it by a computer shop or hook it up to a friend's computer, to see if it's detected and works. Then you'll know whether to have it serviced, or if you have to install a driver from the CD or the net. You can get drivers and help here at Samsung Support:
http://www.samsung.com/us/support/
Here is another site for drivers:
http://www.nodevice.com/search/search.html?text=Samsung+ML+2010&search_area=all
Good luck, and hope this helps.
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