I could not use my Canon MP 620 printer which is wi-fi connected to my PC. The printer was no longer seen in the printer dialog box. My investigations pointed to the print spool service no longer working and I could get it to start/enable when I went into the services management box under properties. Set point restore didn't solve it. You know the deal is that you Google the problem for solutions hoping for something that will work and voila! A buggy Windows update to improve compatibility issues might be the problem. KB 2762895 came out 11/28/12. I removed it and my printer is back. Amazing, a compatibility fix that screws up compatibility. Thank you Microsoft.