Problem with the computer's PRAM - See Resetting your Mac's PRAM and NVRAM.īoot drive's directory has been corrupted - Repair with Disk Utility.Ĭritical system files are damaged or deleted - Reinstall OS X. In most cases the problems may be caused by: Mac OS X- Gray screen appears during startup Solutions may be found in:Ī flashing question mark appears when you start your Mac Their causes are outlined in Intel-based Mac- Startup sequence and error codes, symbols. These are related but not identical issues. Question (?) Mark, Blinking Folder, or Gray Screen at Startup See Mac OS X- Gray screen or prohibitory sign appears during startup.
