Find your Hard Drive icon on your
desktop (should be in top-right corner),
select it with one click (only), then
choose "Get Info" from the Finder's File
The resulting window shows Hard
Drive capacity, space available and used space. If available space is
getting down to 10-15% of drive capacity,
your drive is full;
less than 10% means trouble is brewing.....
Properly identify your machine by
collecting its system specifications and
details. Just ask your Mac:
Select "About This Mac" under the
Finder's Apple Menu; here you'll find OS
version number, details regarding your
machine's processor(s), installed RAM information, and info about your startup (or boot)
Much more complete and detailed
specs may be found in the System Profile
(click More Info button in the "About..."
window). Here you'll find most anything you
might want to know about your Mac's hardware
Illustrated here is System
Profile's Memory pane showing specifications
on each installed memory module in each
available slot. Equally detailed and
specific information is also available for
every drive, card, bus, port, and device. If
you use a notebook, you'll also find battery
and charging status under "Power."
All Macs have their serial numbers
recorded under "Hardware" at the top of the
System Profile window (where it may be
easily read and copied). Serial number and specs may also
be found on back of notebooks in wee-tiny
print, or on a label inside battery bay of
older laptops with removable batteries.
iMacs have serial number and machine specs
on underside of stand, towers have a label
under side door or on back panel. The
serial number may be used to ascertain
warranty status and further identify machine
For some inexplicable reason, Mac model numbers are seldom
used to identify machines, even tho every
model has one. Machines are best
identified by specs on their labels or in
System Profile, or
by serial number.
Start with an overall examination.
Take nothing for granted.
It might be a good idea to take
notes as you go through the inspection
process. Some steps may seem unnecessary,
but try 'em anyway, just in case. Be
Power down. Disconnect power to CPU and all
Two reasons for this: First, it
eliminates any possibility of damage that
might be caused by
disconnecting/reconnecting powered devices.
Second, removing power from computer and all
components for a minute or so (including
printer, modem, router, and all peripherals)
will cause some devices to reset when
powered on again, thus eliminating a few
possibilities right off the bat. Test and
confirm power from outlets on any surge
suppressors or power supplies (UPS) in use
and/or bypass these.
Disconnect, examine, reconnect each cable.
While things are shut off, take a good look
at all cables, cable ends and ports. Are
contacts clean and shiny, or are they dirty,
dull and oxidized? Are connectors in good
shape and intact? Damaged cables should be
replaced; damaged ports may be another
matter. If necessary, carefully clean
connectors, blow out ports and plugs, then
reconnect each device cable. Make sure plugs
have a snug fit and cables aren't being
strained, twisted or bent.
If a new device has been added
recently - including any internal cards -
remove it and leave that device aside for
now. (Hardware problems often manifest
themselves during startup, causing freezes,
hangs and/or blank screens.)
Reconnect power to
Turn on each peripheral and allow time for
printers, modems, routers (etc.) to go thru
their startup routines. When all external
devices are up and running (typically a
minute or two), reconnect power to the
computer and turn it on. If problem remains,
shutdown your computer, disconnect power and
replace/reconnect cards/devices one-by-one,
testing startup with each. If problem
reoccurs, the last connected card/device
might be at fault.
If problem never went away or startup to
(desktop) is impossible, the next steps will
be unavailable and you might want to bring
Check System Prefs (if possible).
If you startup to a date/time
error message, your desktop computer's PRAM
battery is probably dead. (Some older
machines may refuse to boot at all with a
dead PRAM battery.) Replacement batteries
are readily available but may require
partial disassembly for access. (Notebooks
have something more like a capacitor than a
battery, and an overnight charge will
refresh most notebook PRAM batteries.) Now
might be a good time to consult your user
Open System Preferences and check
settings in relevant control panels and
panes. Be sure to check the Accounts pane
-> Login Items (or Startup Items) and
make sure there isn't something launching on
startup that might be the culprit. NOTE: Now
is not the time to change anything other
than those settings that may be related to
the specific problem you are experiencing;
you're likely to see login items installed
by your OS (iTunes, for example) that should
remain. Third-party (non-Apple) items are
always suspect, especially auto-update
Try to isolate and
identify the problem.
Record any error messages that appear. Is
the problem repeatable? What action or event
preceded the problem? Does it seem to be
related to a specific application? If so,
check the program's preferences (usually
under the Application or Edit menu).
If problem appears to be related
to a peripheral device - printer, scanner,
modem, router, etc. - make sure any suspect
device driver is current by checking its
version numbers and system requirements.
(Drivers on CDs included with most devices
may be unnecessary for use with Macintosh,
or they may be already be outdated at time
of purchase.) If you've done an OS upgrade,
you may need to download/update your device
Collect System Info.
The first item under the Finder's
Apple menu is "About This Mac" and will
identify your Operating System version,
processor info and installed RAM.
Copy down info and identifiers as
it applies to the problem at hand. See
"Collecting System Info" section (top of
this page) for details on where to look and
what to look for.
Before you call for help:
Regardless of where you might turn
for assistance, you'll save yourself time
and trouble by having the following
information readily available (and tech
support doesn't come cheap):
- Machine type (notebook,
iMac or tower), processor type and speed
(XX.XGHz WhatsitCPU), OS version number,
and installed RAM. Hard drive capacity and
available (free) space might be helpful,
- Changes or events related
to the issue, especially anything recent,
and specs for any peripherals involved.
- A record of error
messages, symptoms encountered, and steps
The amount of relevant information
you have on hand when you call tech support
will determine a lot of your success in
receiving help. From a tech's point of view,
it's much easier to have a coherent
conversation when both parties know what
equipment is in use, under which Operating
System, and exactly what error messages or
symptoms are being generated, when, where,
and under what circumstances.
If your Mac is under warranty, you may be
entitled to free tech support - check your
warranty info (also available by serial
number from Apple's support page found here
under Apple links). Most hardware/software
vendors charge for phone/online support by
incident or by the minute. We don't provide
free tech support, either. In fact, it's
rare to diagnose a problem over the phone,
let alone solve it, so we respectfully
request you bring your machine to the shop
for a proper diagnostic evaluation. See our
Service Policies and Ops page for details.
First, be patient; the beachball
cursor is there to indicate machine is busy.
But, if it seems stuck after awhile, there's
a "Force Quit..." command under the Apple
(logo) menu that should get you out of it.
If that's not an option, you might have to
force shutdown by pressing/holding power
button for 6+ seconds which will end a hang
and shutdown machine - but does nothing to
prevent it from happening again under same
circumstances (unless it was just a fluke).
If you want to prevent beachballs in the
future, or you find it's happening far too
often, then something needs to change.
And the cause is...?
Common software causes (with easy
- A cluttered desktop
littered with folders full of pics or
music or videos, misplaced apps and huge
downloads can slow things down. File
things where they belong - in the drive
- and clean up that desktop. Empty the
- Using 'List View' with
file size displayed. Use Column View
instead (Finder > View menu) or, if
you prefer List View, uncheck "Size"
under View Options at bottom of the
Finder's View menu.
- Running too many apps at
once. Closing windows does not quit an
application; when you're done with an
app, choose "Quit" from the app's menu
or press Command+Q on the keyboard.
- Unnecessary anti-virus
and utility apps. Anti-virus apps insert
themselves into practically everything
you do, and will slow things to a crawl
with little or no benefit. Legitimate AV
programs will have an uninstaller
attached - use it.
"Slow" is a pretty vague
complaint, helps to know if it's related to
a particular program - web browsers for
example. Browsers collect a lot of so-called
"cruft" these days, a term encompassing
cookies, history, location info, icons,
autofill and other web data. Safari has a
Reset function conveniently located in the
Safari menu that can clear out most of it
with one click, a good habit to get into
these days when quitting Safari. (Other
browsers have similar functions typically
buried under their preference settings.) If
machine slowness is system-wide and not
limited to a particular app, a little more
investigation is required but it can usually
be sorted out quickly here on the bench.
More complex causes, including
Utilities and trouble-shooting
apps can do more harm than good when
installed and run unnecessarily or
improperly. Purloined programs downloaded
from suspect sources (torrent or
"file-sharing" sites) are always suspect
and frequently cause trouble - which is to
be expected - but there are also some apps
around that are just plain nasty. One prime example is MacKeeper, an
insidious scam from an unscrupulous vendor
that can be very difficult to remove. If
you were unfortunate enough to download
and install any version of MacKeeper, this
link may help you lose it and get your Mac
MacKeeper's uninstall process leaves some
files behind that can tie-up the CPU by
throwing relentless errors, thereby
creating the very problem it pretends to
solve. Intentional? You might think so if
you saw it in action.
There are some great utilities out there
that actually do what they're supposed to
do, many of which are typically little
more than a nice user interface applied to
UNIX functions built into your OS (no harm
in making maintenance routines more
is a great, simple "cleanup" utility as is
is also excellent and has lots of
functions and options and monitoring apps.
If you feel you _must_ install anti-virus
comes highly recommended, but be aware
that any anti-virus app will slow
operations as it performs scans and
executes its duties.
Hardware: How much memory (RAM)
In ballpark numbers, 1-2GB RAM is
barely adequate these days, and 2GB is
minimum requirement for OS 10.7/10.8/10.9.
(See Collecting Specs, above.) RAM is
working space, and if the OS is taking it
all, there won't be any left for other apps
to use. If you upgrade your software/OS, be
sure to check RAM requirements and upgrade
accordingly. Freezes may be caused by an
application running out of memory, or too
many apps running simultaneously. (Polite
apps might warn you before they run out of
memory, but don't count on it.) Amount of
RAM required depends on what you use your
computer for, of course, and some apps
require much more RAM than others. Check
your Dock and quit the apps you're not
using. Or maybe it's time to restart?
possible causes related to slow,
unresponsive Macs include failing hard
drives, corrupt (damaged) or missing System
segments, wacky application software,
optical drives or peripherals gone wild, and
a whole slew of other things. A damaged
input device can mimic a freeze, too. Bring
it in and we'll figure out what's slowing
Check System Prefs > Network,
and Mail.app prefs.
Possibly the most common complaint
comes from people who suddenly are unable to
send and/or receive email. The problem might
well be on your server's end, especially if
none of your machine's settings have been
changed, all cables and devices are intact -
and you're in Nevada
County. If it just
keeps asking for your password, and you haven't changed anything,
the problem is probably not on your end.
Sometimes all you can do is wait a day or so
and try again. A lot of changes are going on
with ISPs, too, as they begin to meter data
transmission, throttle bandwidth and
calculate extra charges for connected
devices. The better ISPs out there post
system status bulletins on their web sites
(if you can get online). Lesser ISPs like Ma
Bell and Comcast should have phone numbers
on their bills for outage and status info.
Good luck w'that.
An enormously helpful Apple Mail support
page may be found here: Mail.
It's important to make the distinction
between ISPs and ESPs:
Internet Service Providers (ISPs) = Comcast,
ATT, Cox, Hughes, Wildblue, etcetera; these
are cable, phone, satellite and microwave
Email Service Providers (ESPs) = Yahoo,
Google, Hotmail, et al.
If you can't get online at all, it might be
your ISP. If you can't get mail, it might be
either. Try web mail: Launch a browser
(Safari), go to ESP's server and login to
your mail. That might narrow things down.
If you're on a wireless (AirPort or WiFi)
network, your AP menu and/or Network pane in
System Preferences should show name and
status of your selected network. If so, your
Mac and router are communicating and the
problem is somewhere between router, modem
and ISP. If you use a notebook, take it out
on the town and try connecting to a
different network at a coffee house or a
friend's location. Might be a good time to
write down the settings you see, too (port
numbers, SSL on/off, DNS numbers, etc.), but
don't change anything unless you know what
sometimes fail, as do routers, and most have
lights indicating status. A damaged modem
may report any number of odd (sometimes
misleading) errors, it may endlessly try to
connect or disconnect, its power supply may
have failed, or your network prefs pane may
insist that there is no device connected.
Try resetting both modem and router (no harm
in doing this):
- Shutdown your computer
and remove power (unplug) modem, router
and/or gateway. Take
a moment to check all other
- Wait a minute or two,
then reconnect power to modem, then to
the router. After these gizmos have
completed their startup routines (about
a minute or so), cross your fingers and
startup your Mac.
- If communications have
been restored, you're good to go.
- If not, and you haven't
changed any email send/receive or
username/password settings, then either
your ISP is temporarily offline or there
might be a hardware/software issue that
needs further evaluation.
Make sure all connections are
intact and power is on.
Sometimes it helps to power-up
printers and peripherals _before_ starting
up your computer. Check printer's ink tanks
or cartridge. Look for any physical damage
to the device, its cables and ports, make
sure everything is properly connected. Power up peripherals, wait a
minute or so, then power on your computer.
Check settings; make sure your printer
appears in Printer List (System Prefs ->
Printer and Fax -> Setup), make sure
external drives and devices are mounted and
If printer is producing distorted
output (too small or too large, sideways,
missing fonts or styles), check Page Layout
settings (in File menu) in the application
you are printing from. If output appears as
a page of gibberish, or machine spews out
blank pages along with the desired job, or
output problem persists, try printing
something from a different application. For
example, launch TextEdit, type something,
and see if that prints properly. If so, the
problem is app-specific. If not, your
printer (and/or its driver) is at fault. If
you've recently upgraded your OS, you may
need to download and install or update to a
newer driver. (Same may be true of scanners
and other devices.) Consult your printer's
manual and try running printer's self-test
to see if the printer itself is
If you are trying to print a page
from some web site, know that web pages are
not necessarily designed to be printed and
printer output might be spread over multiple
pages in ways you wouldn't expect, or you
may only be able to print a portion of the
page's layout due to frames, tables and
other design elements. There are workarounds
for this - but don't blame your printer.
Sometimes there's just nothing to
This message appeared one day for
no apparent reason, with no workaround.
Tried every way possible to save this
document - Photoshop simply refused access
to anything, no matter what. Sure, blame it
on the disk. And no, it's certainly not OK.
Check and fine-tune your
Adjustments in System Preferences
will frequently solve display "problems,"
while various view options (including those
in Finder's View menu and Finder
Preferences). Some commands can show or hide
controls, so sometimes you need to make
controls available in order to change them.
Clockwise from top: Disk
Utility, Finder Prefs, System Prefs, and
Get Info windows from OSX
Review System Preferences:
Your System Preferences
control the appearance and operation of
your machine's Operating System. System
Prefs are available from the Apple menu
and from its icon in the Dock at the
edge of your screen (both illustrated at
Accounts, date/time, desktop
color/image and screen saver options,
Dock settings, network settings (email
and internet), printer, keyboard and
mouse, startup disk and most other
controls are located in System Prefs.
Each of these controls can be changed
and customized to suite each user;
settings are specific to each user
By the Way, while we're on the
Many people think clicking a close
button in a window's top-left corner () is the same as quitting
the application. It isn't. It merely
closes the window (in most cases),
leaving the application open, active and
running. Why is this important? Because
applications load into memory (RAM) when
launched, and quitting unused
applications frees up precious RAM.
Instead of clicking the close box when
finished with an application, choose
Quit from the File menu, or type
(Having said that, I should
point out an inconsistency with the
close button: Sometimes it _does_ cause
an app to quit in addition to closing a
window, as is the case with System
Preferences and a few other
System-related windows. Just make sure
you quit apps when finished with 'em.)
Run Disk Utility periodically.
-> Utilities folder is the Disk Utility
application. Running Disk Utility to verify
your hard drive and repair permissions can
fix many minor errors before they become
Check PRAM Battery (aka "backup" or "clock"
your desktop Mac is 5-years-old or more, its
internal battery may be getting weak.
Symptoms include a date/time error on
startup, preference settings that may revert
to defaults, and possible startup issues
(very rare). Older Mac desktop machines use
a 3.6v, half-AA-size lithium battery, while
newer Macs have a 3v CR2032 button battery.
Replacing a battery is an easy
do-it-yourself fix for tower machines
(PowerMacs and Mac Pros), just make sure to
note polarity when removing old battery.
iMacs require disassembly and some expertise
to access the battery - the newer the
machine, the more difficult it is to replace
its battery. If your iMac has an aluminum
case, it requires removal of glass face and
display screen to access the PRAM battery.
Real new models (those lacking CD/DVD
drives) may use adhesive to secure glass,
making access even more difficult. Check
your user manual or look your machine up
online to see what's involved regarding your
Notebook Macs don't have PRAM batteries as
such; they rely on machine's main battery to
maintain settings (incl. date/time). Older
laptops may have a capacitor instead of a
PRAM battery (so that main battery can be
removed and replaced without losing
settings), but new MacBooks don't even have
capacitors. Instead, Apple has decided to
prevent battery removal altogether by
placing it behind bottom case and securing
it with tamper-proof fasteners or adhesive.
Fan noise and/or excessive heat:
or laptop, all computers have fans in them
these days because their processors
typically run at 140-150ºF or more. And they
all collect dust eventually.
photo shows a removed fan from a MacBook Pro
and the dust it left behind. Fan's exhaust
vent is almost completely blocked with a
half-inch buildup in right corner. Those
fins carry heat from machine's heatsink to
the fan, but they can also catch any fuzz
from blankets, pets or clothing that may
happen to pass by. Whenever any machine gets
disassembled here at the shop for any reason
- desktop, tower or laptop - we thoroughly
clean fans, vents and interior because they
all get dusty over time, and a good cleaning
can add years to a machine's life. In this
case, the fan itself began to make noise and
had to be replaced.
All Macs have sensors within them to protect
machine from overheating. You may get a
warning - or not - but machine will put
itself to sleep if it senses an overtemp
condition, and/or shut itself off if
necessary. Fans will ramp-up as needed,
usually running at idle speeds during normal
use, but when they go full-tilt you'll
certainly hear them. If your Mac is making
noise, getting abnormally hot or fans are
running at high-speed all the time, it may
be due for a cleaning.
Clear web browser cache:
has a simple and convenient menu item that
empties Safari's cache (right), and another
menu command just above it - Reset Safari -
that will clear a slew or other records and
settings, including history, auto-fill and
every other modification made to Safari
(except bookmarks), setting it back to its
original, unused state.
and other browsers also allow you to clear
the cache, but the command is typically
buried somewhere in browser preferences and
can be hard to find.
Clean out old emails:
seen mail apps so stuffed with old email -
including unemptied trash and spam - that
messages number in the tens of thousands.
Nobody has time to sort thru all that. Get
rid of it! Clear out that inbox, empty the
trash, delete all that spam. Your inbox
should be kept empty, with incoming emails
either deleted, saved to a mail folder, or
otherwise dealt with every time you retrieve
Archive old mail you
wish to keep:
you like, you can collect and export old
emails from Mail to a TextEdit file,
including email photos, graphics and live
links. Here's how:
First, select the messages you wish to save;
the idea is to get them all into a single group,
so you might want to create a Mail folder to
contain them, then drag messages into the
new folder. Select all messages by clicking
the first one, scroll down to the last
message, hold down Shift key and click last
With all messages selected, choose "Save
As..." in Mail's File menu. From the
resulting dialog box (right) give the file a
name, select a destination, and be sure to
save in Rich Text Format (to preserve
links), then check the "Include Attachments"
box to preserve all images and attachments -
inline - with your messages.
Five easy reasons
to clean up those files:
- Your primary hard drive -
or boot volume, if you prefer - requires a
certain amount of free space to run
efficiently. Deleting unused/unwanted
files frees up space for file and volume
optimization processes to take place. A
crowded, near-full hard drive will be
sluggish; a full drive will eventually
refuse to even startup.
- Searching thru organized
files is easy. When you save a file, pay
close attention to where it is going, and
be sure to send it into the proper folder
where it belongs. Whatever scheme you use
to sort and organize things is fine, as
long as it works for you. The Operating
System creates a Home Folder for each
user, along with root-level folders for
Applications, Documents, Music, Pictures,
Movies and the like, and that's a good
place to start.
- A neat, well-organized
drive makes for a neat, well-organized
backup. Get all that junk off your desktop
or you'll be seeing double when you mount
your backup drive (duh!). Empty trash
(including email and browser cache), run
Disk Utility's First Aid now and then. You
_do_ have a backup plan in place, right?
- A nicely organized drive
lends itself well to customization. A nice
desktop photo and screen saver, custom
window colors and fonts..... Since you'll
be creating special folders to hold
special files, why not create custom
folder icons while you're at it? If you're
creative and resourceful enough, have at
it. Google "custom OSX icons" for ideas
and custom icons if you like.
- If a drive fails - Heaven
forbid! - a tech will have a much better
chance of recovering your data if your
files are well organized and properly
stored under named Admin accounts.
Directories get overrun, drives go wonky,
video and music and photo libraries grow
at alarming rates, things can ugly in a
hurry. Good thing you have a backup, huh.
you leave your computer running day and
night, automated maintenance routines will
run periodically - daily, weekly and monthly
- as they are designed to do (usually in the
wee hours of the morning). If not, and you
are familiar with the Terminal application,
you probably know the commands to execute
these routines, bit if you're like most Mac
users you'll want a graphical interface to
these commands. A few recommended utilities
are listed below. Some of these also include
a few additional System tweaks and tricks. NOTE: Be
sure to match utility version to your OS
Startup issues are best handled by
exploring all the easy solutions before moving on to more
complicated suspects. Start with status of
the boot volume. If it's a notebook, has it
been dropped or damaged? Will it boot from
your OS disc or Lion flash drive?
Simple as it may sound, failure on
startup arrives in a variety of ways with a
variety of symptoms (and clues). Try to
answer these questions:
- Did you hear the normal
startup sound? No sound (is sound turned
down or off)? A different sound, a tone or
beeps perhaps? How many beeps?
- Does the power button
light up? Does it stay on or go off when
released? Is it pulsing? Does any sound at
all come from the CPU (fans, drives
spinning, other noises)?
- Does an icon appear
onscreen? If so, what does it look like?
If it hangs, what's on the screen? Is the
screen black, blue, or gray? What is the
cursor doing? Do
you get a message saying that you need to
restart in four languages? (If so, sorry.
See Kernel Panics, below.....)
- How far do you get?
Nowhere (black screen), to the Apple logo,
to a blank gray, white or blue screen, to
the desktop? What's on the desktop, what's
in the menu bar? Anything launching on
you've checked all the usual suspects and
machine still refuses to boot, try starting
up from your (OS-version appropriate <-important!) System
Set your Startup Disk (in System
- Insert your System Install
CD/DVD into the optical drive.
- If machine is on, shutdown
(hold power button down for 5 seconds).
- Sometimes waiting 5-10
minutes with power disconnected helps.
- Startup from optical drive
by pressing "C" key during startup.
- When you arrive at the
Installer, ignore it and launch Disk
Utility from the menu bar.
- Select your hard disk in
DU's window and run Disk Repair function.
- If repairs complete
successfully, restart. You're all done!
- If you're stuck, call for
an appointment and bring it on in.....
If your startup volume is not
specified in your System Prefs, your Mac may
take quite awhile to startup as it searches
all connected volumes for an OS; check your
Startup Disk setting and make sure the
proper volume is selected (as illustrated
Some machines will not boot at
all without a specified volume. If this
applies to you, boot from
(version-appropriate) System disc (hold "C"
key during startup with bootable disk in
drive), and set startup disk from the menu
Pay special attention to the Operating
Having more than one Operating
System per volume is not a good idea. In
fact, it can be a disaster. (The lone
exception, of course, was OSX + OS9 Classic
Even if Disk Utilities passes all
tests, various hardware tests pass,
everything comes up OK, doesn't mean your
Operating System is undamaged; a battered OS
can certainly prevent normal startup but
might not produce errors in Disk Utility.
Before doing anything drastic (like
replacing your OS) and running the risk of
making matters worse, call for an
appointment and bring it in!
Kernel Panic (KP).
With instructions to restart in
four languages, a Kernel Panic doesn't give
you any other choice. Sometimes, a restart
is, in fact, all that is needed and things
will return to normal. If it appears again
after a restart, something more serious has
Before putting yourself (and your
Mac) thru the trials listed below, you might
save yourself the trouble of trying to deal
with a KP yourself and bring the machine to
our shop for service. Having said that,
presented below - for information purposes
only - are a few basic steps toward
diagnosing possible causes of a Kernel
Panic. What follows is a brief test using
System install DVD that came with your
computer or was used to upgrade (up to OS
10.6.x), or using the recovery partition (OS
10.7 and later).
First, shut off
computer and disconnect all attached
devices. Then startup machine and see the KP
has gone away. Yes = suspect external
device, no = internal problem. Normal
troubleshooting routines start by checking
simple things first in search of a quick
fix, but troubleshooting Kernel Panics is a
little different. By eliminating connected
hardware components, we are eliminating them
as possible causes. They can be reconnected,
one at a time, and tested individually if KP
is solved without them.
Do not attempt to make repairs from any
than your Operating System. Newer utilities
should be okay, but anything older than your
OS will likely fail or may do damage.
and earlier Systems: Startup from
the OS DVD used to install your OS and run
Disk Utility on your hard drive. It's worth
saying again: At the first hint of any
trouble, run Disk Utility to check hard disk
and repair permissions, if possible. If disk
repair is necessary, you'll have to boot
from OS DVD in order to repair your hard
later: Press and hold Option key
immediately on powering on and select
recovery partition for startup. Then run
Disk Utility on your hard drive from
KPs in general:
These can be indicative of both
hardware and software problems, making them
rather difficult to troubleshoot. One
possible cause is defective or failed memory
(RAM). Other causes include damaged ports,
connectors, and peripheral devices; failed,
failing or corrupt hard drives; and failed
or damaged video cards, cables/connections,
or -worst case - logic boards.
If hardware is not the cause,
other suspects include corrupt, damaged or
missing Operating System, firmware issues,
device drivers, corrupt fonts, and
incompatible application programs. The list
goes on and on.....
KP while running, versus KP on startup:
The timing of a KP's appearance
can be a significant clue as to its cause.
If KPs appear during the course of
operation, it might be connected to use of a
particular application, a specific OS
component, or a device driver. If so,
uninstalling and/or reinstalling (or
updating) the suspect software might return
your machine to normal. If you're not sure
about deleting things, don't. You can
temporarily move a file to the trash and
thereby deactivate it on restart - without
emptying the trash and actually deleting it.
Just make a note of file's original location
so that it can be returned to its proper
If a KP appears on startup - on
each and every startup - the problem is
probably more serious. It might still be a
software issue of some nature, but more
often than not it will turn out to be
Recent changes might suggest cause.
With so many potential causes, it
might be helpful to recall events
immediately preceding the appearance of a
Kernel Panic. Any recent changes, additions
or hardware/software installations may have
been the cause; KPs might not appear until
your next startup, so go back to the last
change that was made before shutdown.
Run Apple Hardware Test (up to OS
Try booting from Apple Hardware
Test (AHT) located on disk 1 of the DVDs
that came with your Mac (up to OS 10.6 - AHT
is unavailable for later versions): Insert
disk 1, and startup while holding down the
"D" key, or use Option key (Startup
Manager), select AHT and continue startup.
With some OS versions, AHT is on a separate
(usually silver) disc that will have "AHT"
printed on its label. Examine contents of
the System Profile tab to make sure all
devices are properly identified. Next, run
the Quick Test. If the Quick Test turns up
nothing, try the Extended Test; if no error
is produced, you might try letting it loop a
few times. AHT may indicate a hardware
issue, but it does not test software.
tests pass without error, and all hardware
is properly identified, that - sadly -
does not mean everything is A-OK. We've
had machines refuse to boot from anything
_except_ AHT (including the OS Install
disc) but all AHT tests passed with flying