Hi, One of our users has a problem with his MacBook Air. Upon booting, he gets an error message saying: Panic (cpu 0 caller 0xffffff802e259241): "Unable to find driver for this platform:\"ACPI\".\n"@/SourceCache/xnu/xnu-2050.20.9/iokit/Kernel/IOPlatformExpert.cpp:1548.....BSD process name corresponding to current thread: Unknown. To give you some background, he had an iPhone with a locked sim (they were trying to retrieve the pin) and he contacted O2. O2 told him to connect the iPhone to the MacBook Air, which was working correctly at the time. He said that the MacBook seemed to start a download or update of some sort and the next time it restarted, it had this error. I have tried pressing CMD + S at startup in order to try fsck -y and it presents me with screen saying Loading drivers........and then a similar screen to the one above and won't accept any input. I tried CMD + OPTION + O + F at startup but couldn't get to the EFI. Can you tell me if I need third party software instead and if I go messing with the EFI, will I void the warranty? Thank you very much in advance for any advice that you can provide, Justin Forde.