Out of the blue my MBP will stop connecting to my router. I know the router is fine because my 2010 MBP (which I regrettably sold) worked flawlessly with this router. When I restart the MBP, it sometimes fixes the problem, but most of the time I am prompted to enter the network's password (despite that the MBP is set up to remember it) ... When I enter this password, I am sure it is correct (all other devices connect to the router using that password), but my MBP refuses it. What is going on here?