I had the same issue REPEATEDLY with my 15" early 2011 MBP. I tried all of the software fixes, resetting PRAM, etc. Even had it serviced multiple times by Apple. Didn't matter what version of OS X I was running, I always ran into the "No Hardware" issue. But I finally found the solution. It's 100% hardware in mine and many other's cases. The problem is the wifi/Bluetooth cable. It runs over the disc drive and is prone to failure. Check out http://warrantyvoidifremoved.blogspot.co...-intermittent-wifiwireless-on.html?m=1 for the full fix instructions.