Apple Mac mini (Mac OS X Server, Late 2009) - Manual (Page 37)

Chapter 3 Problem, Meet Solution 37
If your Mac mini freezes during startup or you see a flashing question mark
 Wait a few seconds. If your Mac mini doesn’t start up after a delay, shut down your
Mac mini by pressing and holding the power (®) button for about 5 seconds, until it
shuts down. Then hold down the Option key and press the power (®) button again
to start up your computer. Keep holding down the Option key until your Mac mini
starts up, then click the arrow under the icon of the hard disk you want to use as your
startup disk.
 After your Mac mini starts up, open System Preferences and click Startup Disk.
Select a local Mac OS X Server System folder.
 If the problem occurs frequently, you may need to reinstall your system software
(see “Reinstalling Software Using Remote Install Mac OS X” on page 38).
If your Mac mini doesn’t turn on or start up
 Make sure the power cord is plugged into your Mac mini and into a functioning
power outlet, and the power cord is plugged into the power adapter.
 Press the power (®) button and immediately hold down the Command (x), Option,
P, and R keys on an Apple keyboard until you hear the startup sound a second time.
This resets the parameter RAM (PRAM). On other keyboards, press the power (®)
button and immediately hold down the Windows, Alt, P, and R keys.
 Unplug the power cord and wait at least 30 seconds. Plug the power cord back in
and press the power (®) button again to start up your Mac mini.
 If you still can’t start up your Mac mini, see “Learning More, Service, and Support” on
page 46 for information about contacting Apple for service.