Apple Imac 21 5inch Late 2011 User Guide

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Chapter 4      Problem, Meet Solution
An Ounce of Prevention
If	you	have	a	problem	with	your	computer	or	software, 	having	kept	up-to-date	Time	
Machine	backups	ensures	that	your	data	won’t	be	lost. 	If	you	make	regular	Time	
Machine	backups, 	you	can	restore	your	software	and	all	your	data	to	exactly	the	way	it	
was	at	the	time	of	backup. 	Even	serious	issues	are	of	less	concern	when	you	safeguard	
your	information	with	 Time	Machine.
Problems That Prevent You from Using Your iMac
If your iMac won’t respond or the pointer won’t move
	
ÂMake	sure	the	mouse	and	keyboard	are	connected. 	Unplug	and	then	plug	in	the	
connectors	and	make	sure	they	are	secure.
	
ÂTry	to	force	problem	applications	to	quit. 	Hold	down	the	Option	and	Command	(x)	
keys	and	press	the	Esc	key. 	If	a	dialog	appears,	select	the	application	and	click	Force	
Quit. 	Then	restart	your	iMac	to	be	sure	the	problem	is	entirely	cleared	up.
	
ÂIf	you’re	unable	to	force	the	application	to	quit, 	hold	down	the	power	button	(®)	on	
the	back	of	your	iMac	for	five	seconds	to	shut	down	the	computer. 	
	
ÂUnplug	the	power	cord	from	your	iMac. 	Then	plug	the	power	cord	back	in	and	press	
the	power	button	(®)	on	your	iMac	to	turn	it	on.
If	the	problem	reoccurs	when	you	use	a	particular	application, 	check	with	the	
application’s	manufacturer	to	see	if	the	application	is	compatible	with	your	iMac. 
						

							42Chapter 4      Problem, Meet Solution
For	information	about	the	software	that	came	with	your	iMac, 	go	to		
www.apple.com/downloads.
If	the	problem	occurs	frequently, 	try	repairing	your	disk,	restoring	your	software	from	
a	backup, 	or	reinstalling	your	system	software	using	the	Mac	OS	X	Utilities	application	
(see	 “Repairing, 	Restoring,	or	Reinstalling	Mac	OS	X	Software” 	on	page	44).
If your iMac freezes during startup or you see a flashing question mark
	
ÂWait	a	few	seconds. 	If	your	iMac	doesn’t	start	up	after	a	delay, 	press	and	hold	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	 iMac. 	Keep	 holding	
down	the	Option	key	until	your	iMac	starts	up, 	then	click	the	arrow	under	the	icon	of	
the	startup	disk	you	want	to	use.
After	your	iMac	starts	up, 	open	System	Preferences	and	click	Startup	Disk. 	Select	a	
local	Mac	OS	X	System	folder.
	
ÂIf	the	problem	occurs	frequently, 	you	may	need	to	reinstall	your	system	software	
(see	 “Repairing, 	Restoring,	or	Reinstalling	Mac	OS	X	Software” 	on	page	44).
If your iMac won’t turn on or start up
	
ÂMake	sure	the	power	cord	is	plugged	into	your	iMac	and	a	functioning	power	outlet. 	
	
ÂRestart	your	computer	while	holding	down	the	Command	(x)	and	R	keys, 	until	the	
computer	restarts. 	When	the	Mac	OS	X	Utilities	pane	appears, 	select	an	option	to	
repair	your	disk, 	restore	your	software, 	or	reinstall	Mac	OS	X	and	Apple	applications. 	
For	more	information, 	see	“Repairing, 	Restoring,	or	Reinstalling	Mac	OS	X	Software” 	on	
page	44. 
						

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Chapter 4      Problem, Meet Solution
	
ÂPress	the	power	button	(®)	and	immediately	hold	down	the	Command	(x), 	
Option, 	P,	and	R	keys	until	you	hear	the	startup	sound	a	second	time. 	This	resets	the	
parameter	RAM	(PRAM). 	
	
ÂIf	you	recently	installed	memory, 	and	your	iMac	sounds	tones	every	five	seconds, 	
make	sure	that	the	memory	is	correctly	installed	and	that	it	is	compatible	with	your	
iMac. 	Check	whether	removing	the	memory	you	installed	allows	your	iMac	to	start	
up	(see	page	38).
	
ÂUnplug	the	power	cord	and	wait	at	least	30	seconds. 	Plug	the	power	cord	in	again	
and	press	the	power	button	(®)	to	start	up	your	iMac. 	
	
ÂIf	you	still	can’t	start	up	your	iMac, 	see	“Learning	More, 	Service,	and	Support” 	on	
page	54	for	information	about	contacting	Apple	for	service.
If you have trouble inserting a disc
	
ÂUsing	a	continuous	motion, 	push	the	disc	into	the	drive	until	your	fingers	touch	the	
edge	of	your	iMac.
	
ÂUse	only	a	standard-size	disc. 	
If you have trouble ejecting a disc
	
ÂQuit	any	applications	that	may	be	using	the	disc, 	and	then	press	the	Media	
Eject	key	(C)	on	your	keyboard.
	
ÂOpen	a	Finder	window	and	click	the	eject	icon	next	to	the	disc	icon	in	the		
sidebar, 	or	drag	the	disc	icon	from	the	desktop	to	the	 Trash. 
						

							44Chapter 4      Problem, Meet Solution
	
ÂLog	out	from	your	user	account	by	choosing	Apple	()	>	Log	Out	 “User”	(your	
account	name	appears	in	the	menu), 	and	then	press	the	Media	Eject	key	(C)	on	
your	keyboard.
	
ÂRestart	your	iMac	while	holding	down	the	mouse	button.
If you have trouble scrolling with your mouse
	
ÂIf	you	have	a	mouse	with	a	scroll	ball	and	the	scrolling	feels	rough	or	the	scroll	ball	
isn’t	scrolling	up, 	down,	or	side-to-side, 	hold	the	mouse	upside-down	and	roll	the	ball	
vigorously	while	cleaning.
	
ÂFor	more	information, 	see	““Cleaning	 Your	Mouse” 	on	page	64
If your date and time settings get lost repeatedly
	
ÂYou	may	need	to	have	the	internal	backup	battery	replaced. 	For	information	about	
contacting	Apple	for	service, 	see	“Learning	More, 	Service,	and	Support” 	on	page	54.
Repairing, Restoring, or Reinstalling Mac OS X Software
If	you	have	a	problem	with	your	Mac	software	or	hardware, 	Mac	OS	X	provides	repair	
and	restore	utilities	that	may	eliminate	problems	and	can	even	restore	your	software	
to	its	original	factory	settings. 	You	can	access	these	utilities	from	the	Mac	OS	X	Utilities	
application, 	even	if	your	computer	isn’t	starting	up	correctly. 
						

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Chapter 4      Problem, Meet Solution
Use	the	Mac	OS	X	Utilities	application	to:
	
ÂRestore	your	software	and	data	from	a	 Time	Machine	backup.
	
ÂReinstall	Mac	OS	X	and	Apple	applications.
	
ÂRestore	your	computer	to	its	factory	settings	by	erasing	its	disk	and	reinstalling	
Mac	OS	X	and	your	Apple	applications.
	
ÂRepair	your	computer’s	disk	using	Disk	Utility.
If	your	computer	detects	a	problem, 	it	opens	the	Mac	OS	X	Utilities	application	
automatically. 	You	can	also	open	the	application	manually	by	restarting	your	computer. 
						

							46Chapter 4      Problem, Meet Solution
To open the Mac OS X Utilities application:
	
mRestart	your	computer	while	holding	down	the	Command	(x)	and	R	keys.
Some	utilities	in	the	Mac	OS	X	Utilities	application	require	access	to	the	Internet	and	
the	Mac	App	Store. 	You	may	need	to	make	sure	your	computer	is	connected	to	the	
Internet	by	using	your	Ethernet	or	 Wi-Fi	network.	
To connect by using a Wi-Fi network:
1  Choose	a	network	from	the	 Wi-Fi	status	menu	in	the	upper-right	corner	of	the	screen.
2  If	necessary, 	type	the	network	password.
To	join	a	closed	network, 	choose	Join	Other	Network. 	Enter	the	network’s	name	and	
password.
Repairing a Disk with Disk Utility
If	you	have	a	problem	with	your	computer, 	or	if	you	start	your	computer	and	see	the	
Mac	OS	X	Utilities	pane, 	you	may	need	to	repair	your	computer’s	disk.
1  Select	Disk	Utility	in	the	Mac	OS	X	Utilities	pane	and	click	Continue.
2  Select	the	disk	or	partition	in	the	list	on	the	left, 	and	then	click	the	First	Aid	tab.
3  Click	Repair	Disk.
If	Disk	Utility	can’t	repair	the	disk, 	back	up	as	much	of	your	information	as	possible, 	and	
then	follow	the	instructions	in	 “Repairing,	Restoring,	or	Reinstalling	Mac	OS	X	Software” 	
on	page	44.
For	information	about	Disk	Utility	and	its	options, 	see	Help	Center,	or	open	Disk	Utility	
(in	the	Utilities	folder	in	Launchpad)	and	choose	Help	>	Disk	Utility	Help. 	 
						

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Chapter 4      Problem, Meet Solution
Restoring Information Using a Time Machine Backup
You	can	use	the	Restore	utility	to	restore	everything	on	your	computer	to	its	previous	
state	if	you	have	a	 Time	Machine	backup.
Use	your	 Time	Machine	backup	to	restore	information	only	to	the	computer	that	was	
the	source	of	the	backup. 	If	you	want	to	transfer	information	to	a	new	computer, 	use	
Migration	Assistant	(in	the	Utilities	folder	in	Launchpad).
1  If	your	backup	is	on	a	 Time	Capsule,	make	sure	you’re	connected	to	an	Ethernet	or		
Wi-Fi	network. 	( To	connect	to	a	 Wi-Fi	network,	follow	the	instructions	on	page	46.)
2  In	the	Mac	OS	X	Utilities	pane, 	select	Restore	From	Time	Machine	Backup	and	click	
Continue.
3  Select	the	disk	that	contains	the	 Time	Machine	backup,	and	then	follow	the	onscreen	
instructions.
Reinstalling Mac OS X and Apple Applications
Under	some	circumstances, 	you	may	need	to	reinstall	Mac	OS	X	and	Apple	applications. 	
You	can	reinstall	while	keeping	your	files	and	user	settings	intact.
1  Make	sure	your	iMac	is	connected	to	the	Internet	by	using	an	Ethernet	or	 Wi-Fi	
network. 	( To	connect	to	a	 Wi-Fi	network,	follow	the	instructions	on	page	46.)
2  In	the	Mac	OS	X	Utilities	pane, 	select	Reinstall	Mac	OS	X	and	click	Continue.
3  In	the	pane	where	you’re	asked	to	select	a	disk, 	select	your	current	Mac	OS	X	disk	
(in	most	cases, 	it’s	the	only	one	available).
4  To	select	or	deselect	optional	software, 	click	Customize.	
5  Click	Install. 
						

							48Chapter 4      Problem, Meet Solution
You	can	install	Mac	OS	X	without	erasing	the	disk, 	which	saves	your	existing	files	
and	settings, 	or	you	can	erase	the	disk	first, 	which	erases	all	your	data	and	leaves	the	
computer	ready	for	you	to	reinstall	Mac	OS	X	and	Apple	applications.
After	reinstalling	Mac	OS	X, 	you	can	re-download	the	Apple	applications	that	came	
with	your	iMac	and	other	apps	you	purchased	from	the	Mac	App	Store. 	You	can	restore	
your	other	data	and	applications	from	a	 Time	Machine	or	other	backup.
Important:  Apple	recommends	that	you	back	up	the	data	on	the	disk	before	restoring	
software. 	Apple	is	not	responsible	for	any	lost	data.
Restoring Your Computer to Its Factory Settings
When	you	restore	your	computer	to	its	factory	settings, 	everything	on	your	computer	
(your	user	accounts, 	network	settings,	and	all	of	your	files	and	folders)	is	deleted. 	Before	
you	restore, 	back	up	any	files	you	want	to	keep	by	copying	them	to	another	disk. 	
Write	down	your	network	settings	from	Network	preferences	to	make	it	easier	to	get	
connected	again	after	reinstalling	Mac	OS	X.
1  Make	sure	your	iMac	is	connected	to	the	Internet	by	using	an	Ethernet	or	 Wi-Fi	
network. 	( To	connect	to	a	 Wi-Fi	network,	follow	the	instructions	on	page	46.)
2  In	the	Mac	OS	X	Utilities	pane, 	select	Disk	Utility	and	click	Continue.
3  Select	the	disk	in	the	list	on	the	left, 	and	then	click	the	Erase	tab.
4  Select	Mac	OS	Extended	(Journaled)	from	the	Format	pop-up	menu, 	type	a	name	for	
the	disk, 	and	then	click	Erase.
5  After	the	disk	is	erased, 	choose	Disk	Utility	>	Quit	Disk	Utility. 	
6  In	the	Mac	OS	X	Utilities	pane, 	select	Reinstall	Mac	OS	X	and	click	Continue.
7  To	reinstall	Mac	OS	X	and	your	applications, 	follow	the	instructions	in	the	Mac	OS	X	
Installer. 	 
						

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Chapter 4      Problem, Meet Solution
After	reinstalling	Mac	OS	X, 	you	can	re-download	the	Apple	applications	that	came	
with	your	iMac	and	other	apps	you	purchased	from	the	Mac	App	Store. 	You	can	restore	
your	other	data	and	applications	from	a	 Time	Machine	or	other	backup.
Checking for a Hardware Problem
If	you	suspect	a	hardware	problem,	use	the	Apple	Hardware	Test	application	to	help	
determine	if	there’s	a	problem	with	one	of	the	iMac	components. 	
To use Apple Hardware Test:
1  Disconnect	all	external	devices	from	your	iMac, 	except	the	keyboard	and	mouse.		
If	you	have	an	Ethernet	cable	connected, 	disconnect	it.
2  Restart	your	iMac	while	holding	down	the	D	key.
3  When	the	Apple	Hardware	 Test	chooser	screen	appears, 	select	the	language	you	want	
to	use.
4  Press	the	Return	key	or	click	the	right	arrow	button.
5  When	the	Apple	Hardware	 Test	main	screen	appears	(after	about	45	seconds), 	follow	
the	onscreen	instructions.
6  If	Apple	Hardware	 Test	detects	a	problem, 	it	displays	an	error	code. 	Make	a	note	of	the	
error	code	before	pursuing	support	options. 	If	Apple	Hardware	Test	doesn’t	detect	a	
hardware	failure, 	the	problem	may	be	software-related.
Important:  If	the	Apple	Hardware	 Test	window	doesn’t	appear	after	restarting, 	hold	
down	the	Command	(x), 	Option,	and	D	keys	and	restart	the	computer	to	access	the	
Apple	Hardware	 Test	software	from	the	Internet. 	Your	computer	must	be	connected	to	
a	network	that	has	access	to	the	Internet. 
						

							50Chapter 4      Problem, Meet Solution
Problems with Your Internet Connection
The	Network	Setup	Assistant	application	on	your	iMac	can	help	walk	you	through	
setting	up	an	Internet	connection. 	Open	System	Preferences	and	click	Network. 		
Click	the	 “Assist	me” 	button	to	open	Network	Setup	Assistant.
If	you	have	trouble	with	your	Internet	connection, 	you	can	try	the	steps	in	this	section	
for	your	type	of	connection	or	you	can	use	Network	Diagnostics .
To use Network Diagnostics:
1  Choose	Apple	()	>	System	Preferences.
2  Click	Network	and	then	click	 “Assist	me.”	
3  Click	Diagnostics	to	open	Network	Diagnostics.
4  Follow	the	onscreen	instructions.
If	Network	Diagnostics	can’t	resolve	the	problem, 	there	may	be	a	problem	with	the	
Internet	service	provider	(ISP)	you	are	trying	to	connect	to, 	with	an	external	device	you	
are	using	to	connect	to	your	ISP, 	or	with	the	server	you	are	trying	to	access. 	You	can	try	
the	steps	in	the	following	sections.
Cable Modem, DSL Modem, and LAN Internet Connections
Make	sure	all	modem	cables	are	firmly	plugged	in, 	including	the	modem	power	cord,	
the	cable	from	the	modem	to	your	iMac, 	and	the	cable	from	the	modem	to	the	wall	
jack. 	Also	check	the	cables	and	power	supplies	to	any	Ethernet	hubs	or	routers. 	
Turn	off 	your	DSL	or	cable	modem	for	a	few	minutes, 	and	then	turn	it	back	on.	Some	
ISPs	recommend	that	you	unplug	the	modem’s	power	cord. 	If	your	modem	has	a	reset	
button, 	you	can	press	it	either	before	or	after	you	turn	the	power	off 	and	on.