1. Troubleshooti
ng and
Maintenance
Fundamentals
Learning objectives:
1. Make a checklist for
troubleshooting the pc
2. List common problems
and solutions

2. Common Trouble Checklist
Problems with computers can usually come
from mistakes done by people. If the
hardware and software was used
previously, the problem may come from
you or PEOPLEWARE! So, start checking fist
to make sure hardware and software and
even people are all working before calling
for a technician.

3. When troubleshooting your computer, have
the following in mind and check it first
before calling help. These are common
faults which anyone of us could have done.
Checking this will save you a lot of money
and time too.

4. Is your computer plugged in?
 Sometimes, simple checking if the power
cord is plugged to a power source or just
tightening a loose cord will already do the
trick of fixing the computer.
Sometimes, the automatic voltage
regulator (AVR) or uninterruptable power
supple (UPS) or power strip/surge
protector is just turned off.

5. Have you checked all the cords?
 Thepower cord may be working well but
the monitor or keyboard of mouse cords
are not well placed. Check it out too.
Tighten its connection again.

6. How about other connections?
 Okay,the computer turns on, the
monitor, keyboard and mouse works but
you do not have network connection.
Check out, if the Ethernet cable is
plugged to its correct sockets or the
modem/router or network switch is
plugged correctly and turned on. You
may have to unplug and re-plug this
again to make sure and refresh the
connection.

7. Unseated cards
 Yes,you may have Ethernet
cables, routers, modems and switches
working. Still there is no connection. Have
you checked if the network card wiggles?
It may have been unseated from its slot.
You have to open the computer to
properly seat it in the slot for it. Screw it in
again on the proper position if needed.

8. Is the phone working with dial tone?
 Isthe phone jack working? Check out if
an ordinary phone has dial tone to ensure
that you are connected with a telephone
service provider. If a dial tone is not
available, then it is your telephone
connection that has a problem.

9. Do you have ink toner on the printer?
 Youmay have just ran out of these
supplies. Just put it in and the problem is
solved.

10. Have you changed a configuration or
installed some software or device
lately?
 Ifso, check out your installation, this may
be causing the fault. A simple uninstall
and reinstall may be the solution unless
this installation has destroyed a lot in your
computer.

11. USB insertion does not work
 Simplyunplug and re-plug your USB
device to the USB socket or another USB
socket to verify whether the plug to the
device is not working.

12. Boot sequence problem
 What is your setting for boot sequence? Is
it from the hard disk, floppy disk or CD
ROM? This may be the improper start of
your computer. Check the settings for this
to fix the problem.

13. Reboot
 The most common solution to all problems
in the computer is rebooting. Most of the
time, rebooting cures a lot of problems.

14. Common
Problems and
Solutions

15. My monitor is blacked out
 Make sure the monitor is turned on. Try
pressing the power button on the monitor
again.
 Check to see if it’s in sleep mode. Wiggle
the mouse around or press the enter key.
 If the green light is not on in front, check
the power cord connecting the monitor
into the outlet

16. My monitor is blacked out (cont.)
 If the green light is on, check the
brightness level by using the buttons on
the monitor.
 Check the cable connection from the
monitor into the computer or the
equipment that links your computer to the
TV monitor
 If you still have some problems, call your
help desk.

17. I don’t have any sound
 Check the cord in the back of the
computer to see if the speakers are
plugged into the computer. Plug in your
speaker cable and then try adjusting the
volume control (the speaker icon) on the
task bar. Make sure it is not set to mute.
Clicking on the sliding tab should make a
sound.

18. I don’t have any sound (cont.)
 Some speakers have a power plug.
Check to see if the power cord to the
speakers is plugged in and the power light
on the speakers is on.
 Double click on the volume icon on the
task bar and the volume control box
appears. Make sure the mute button at
the bottom is not checked.

19. My machine is stuck and won’t do anything!
 Holddown the ctrl key and the alt key at
the same time and then tap on the
delete key. You will be given a dialog
box. Look and see if you see in
parenthesis by the application you are
working on the following words:
If you see this, then click on the name of
the application and then select END TASK
from the choices in the box below. It may
take a few minutes to comply. You may see
another box saying the application isn’t
responding. Click on END TASK and it will shit
down that particular application.

20. My machine is stuck and won’t do
anything! (cont.)
 If
the ctrl-alt-del combination doesn’t
work, then press the power button on your
machine for a few seconds until the
power is off. Wait until the green light on
your monitor turns amber (usual setting
when CPU is off) before turning it on
again. This will take about 10-15 seconds.
When you reboot, windows should be
working well again.

21. More in-depth
checking of
peripherals

22. Keyboard
(things to check when your keyboard doesn’t respond)
 If your machine when booting, gives off a
constant beeping noise, it is telling you that your
keyboard is not connected or not working. Check
the plug to make sure it’s connected securely. Try
unplugging it and re-plugging it again.
 If there is no response, check the indicator light on
the keyboard. Is it on? Do the lights respond when
you press the caps lock or the num lock key? If
not, maybe your keyboard is broken.
 Is there a key stuck? Gently pry off the cover and
clean it with alcohol. Make sure it is not
connected to your machine when you are
cleaning it.

23. Mouse
 If your mouse starts acting erratic, it could
be an insufficient memory problem.
Reboot and see if that corrects the
problem.
 If your mouse will only move one
way, either vertically or horizontally, your
mouse may need cleaning.
 Optical mice need cleaning of its bottom
every now and then.

24. Printer
 Check the cables first. Unplug and re-plug
the printer into the computers. Be sure the
power cable is plugged in and the outlet
works.
 Check to make sure the correct printer is
selected in the print dialog box. If you are
on a network, you could be sending the
output to a printer in someone else’s room

25. Printer (cont.)
 Can you print a test page directly from the
printer with it unconnected to the computer?
Each manufacturer has a special series of
buttons to hold down for this self-test. Usually
the series will be in the user’s manual
 Can you print from a different application?
Does it only occur with a certain application
or is it not working with anything?
 Reinstall the software. Delete the old drivers
first.

26. A Dead PC
 First check the cable. Unplug it from the
outlet. Re-plug in both sides and try booting it
again.
 Check the wall outlet. Plug something else
into the outlet see if it works.
 Turn the system off and wait 30 seconds and
then try again.
 Reach behind the machine and see if you
feel air blowing out of the power supply. If you
do, then you know the machine is getting
some power.

27. A Dead PC (cont.)
 Look at the keyboard for the indicator lights being
lit up as the machine boots. Report observance to
the technical help.
 Sometimes the monitor has something to do with
the system acting up. Unplug the power cord from
the monitor and the wall and re-plug it. Unplug the
cable from the computer to the monitor and re-
plug it into the monitor. Try rebooting.
 Listen to identify a beeping series if there is
one, take note of the kind of beep and report it to
the technician.
 Turn in all observations to the technician who will
service the unit.

28. Networking
 First check to see if the cable connecting the
network card into the network drop is connected
to the drop and to the computer.
 Check the back of the computer to see of the
network card light is on.
 Check to see if the site you are trying to pull up is
at fault by typing in a common URL to see if it will
make it out to that site.
 Check to see if anyone else’s machine is having
problems. If everyone is, then it could be the entire
office of household block having difficulties. Call
the corresponding helpdesk to check the status of
the internet

29. Networking (cont.)
 If the internet connection is off on a particular
hallway only, a hub connection could be
down or bad.
 If there is only one machine having problems
and the light on the network card is not on, try
plugging another machine that works into
that drop. It could be that particular drop is
bad, or plug the machine that doesn’t seem
to work into a different drop to see if it would
work there.
 Record all data and call technical assistance.

30. Problems with Internet
 If the browser says that the DNS cannot find your
page, check if you have typed it incorrectly or if you
clicked on a working link. If all is in order, try again as
least twice. It may be that there is just a break in your
connection for a while. If it does not work, then the
DNS may be really be non-existent or not in
operation.
 Sometimes instead of a DNS problem, you have a
“Not Found” message. This may mean that the page
may be missing or the link is not working. Try some
other time or some other day. Try also the main
homepage of the site. If you are diligent enough, you
can email the webmaster of the said page and ask
why the page is inactive.

31. Problems with Internet (cont.)
 There are times when you get surprised that the page you
request loads very fast. Sometimes, the pages you request
even load even if you are not connected to the internet.
This can be a cached page and loads from memory. If you
wonder why the page is not updated, try clicking on the
reload button on your browser’s toolbar to make sure that
you are getting the latest of this page from the website.
 If you cannot connect with the ISP, make sure your modem
is switched and connected to a phone line. Check if the
configuration is correct and the same as originally
configured. If apparently connected, check if there is
limited or no connectivity by right-clicking by right-clicking
on the two networked computer picture on near the clock
at the lower right portion of the screen.

32. Problems with Internet (cont.)
 Surfing takes a long time. Sometimes, there is a peak
demand on the internet because there are too
many users. This will slow down the connections since
the requests come simultaneously and use a main
pipe at the same time altogether. Slower modem
speed can also be a cause of slow connection. Too
many graphics on a website also takes time to load.
 Some features on the site do not show or function
properly. There may be plugins, scripts or controls
that are needed on the site. Some browsers have this
be default. Sometimes, they have to be
downloaded. Check if your browser supports this
function.

33. Most Common Error
Codes and Messages on
the Internet

34. Error Message Meaning Solution
400 – Bad Request The uniform resource Make sure the URL you
locator (URL) is not typed is correct (each
accepted or incorrect. letter or character
The server may be non- whether upper or lower
existent or you are not case including special
allowed to access this characters, slashes,
page. tildes and colons)
401 – Unauthorized These are sites that If you have the
requires authority to authority to access a
enter. In the US, some site i.e. if you have a
.gov sites will only allow password, then use it
users coming from .gov carefully and correctly
or .edu to access it. type it to gain access.
Otherwise, no access Otherwise, do no
will be granted. access it if you do not
have any authority

35. Error Message Meaning Solution
403 – Forbidden This page or Solution is the
document is same as error
password number 401
protected or your
domain is not
allowed access
404 – Not found The server you are Verify the URL that
contacting you typed (all
cannot find the characters). Try
document or again. If it does
page you are not work, try other
looking for. It may links on the site
no longer exist or which are working
you typed a just to check if the
wrong URL links do work at all.

36. Error Message Meaning Solution
550 – xxxxxx is not This means that Check all
a known user you reached the characters to see
site’s email server if you typed it
but unfortunately correctly. Try also
either the used is email address
not connected finding tools to
there or there is no verify if the email
user under that address is correct.
name.
Bad File Request The form Try another
requested is either browser to see if
not supported by the problem is still
your browser or there. Otherwise,
there is an error send an email to
the webmaster to
notify him of this
error.

37. Error Message Meaning Solution
Cannot add form This error occurs The Save As
submission to when a save command to save
bookmark list request is issued a page may do
and try to the trick instead of
bookmark the bookmarking
resulting form. This immediately. The
means that even saved form can
though it is a valid be opened again
URL, it cannot by after it is saved
reused to put in then you can add
your bookmark list. it to your
bookmark list.
Connection The host server If you have a
refused by host does not permit password, try
your domain to retyping if slowly
enter. It may be again checking
password each character to
protected too. try to enter the
site.

38. Error Message Meaning Solution
Failed DNS lookup The URL you typed Retype the URL.
is not valid and Try also reloading
cannot be the page. If both
resolved by the does not work,
domain name then maybe the
system. DNS really does
not exist.
File contains no The site does not Wait for a while as
data have webpages the page is being
on it. This may also uploaded. Try
show when you again if it does not
access the site as work now, try
it is being some other time.
uploaded.

39. Error Message Meaning Solution
Helper Application Sound files, movie Sometimes, there will
not found clips, graphics, ZIP be a dialog box
archive files, or any indicating that a
other type of file you helper application is
may be trying to needed for this file to
download is not show up. Download
supported by your this file to allow your
browser browser to support
this file
Host unavailable This may mean that Try clicking the
the server is offline or reload button. If it
down for doesn’t work, try
maintenance again another time.
Host Unknown The server you are Try clicking on the
contacting is not reload button.
connected or has Sometimes, there is a
lost connection. The lapse in the internet
URL typed may also connection.
be incorrect

40. Error Message Meaning Solution
Network connection This is a generic Try clicking the Reload
was refused by the message to say that button and hope you
server the limit of the can connect, If it is
number of people not possible, then try
allowed to connect again some other
to a server is too busy time.
NNTP server error NNTP (Network News Try clicking the Reload
Transfer Protocol) is button on the toolbar.
the predominant If it does not work, try
protocol used by again some other
computers (servers time.
and clients) for
managing the notes
posted on
newsgroups. An NNTP
server is part of your
ISP’s software, so if this
error occurs, the
software may be
malfunctioning or the
newsgroup does not
exist

41. Error Message Meaning Solution
Permission denied The site may be Observe correct
busy of FTP is not procedure for
allowed when you uploading and
are connected to downloading files.
an FTP site for Keep trying to
uploading or upload or
downloading files download.
Otherwise,
contact the site’s
webmaster to
report this
problem
Too many You may need to Try clicking the
connections – try wait for your turn Reload button on
again later. since the limit of the toolbar. If it
the number of does not work, try
connections to again some other
this server has time.
been exceeded

42. Error Message Meaning Solution
Too many users Webmasters may Keep trying. Try
have set the clicking the
number of users to Reload button on
a website. It may the toolbar. If it
have reached the does not work, try
limit. again some other
time.
Unable to locate The site is either The internet may
host or server down or under have an
maintenance. intermittent
Connection to this problem. Check
server may have your internet
been lost too connection too
and try again.
Check also if you
have typed a
correct URL

43. Error Message Meaning Solution
Viewer not found This file type Try getting the
cannot be viewed viewer or try
with your browser loading the file
using another
browser
You can’t log on This is for Try again to
as an anonymous connection to connect. Make
user and FTP server. sure you have the
Anonymous correct username
access is not and password.
allowed as
indicated.