Members who are
unable to attend the General Meeting may submit questions to
"askdacs@dacs.org" by the day prior
to the meeting. We will attempt to get an answer for you. Please
provide enough detail, as we will not be able to ask for additional
information.
Q. My wife has had a laptop computer for about 9 months, and everything has been fine until just
lately, when she has lost most of her desktop icons. They are just gone. She had run a utility that
was supposed to clean up unused files. I managed somehow to bring the icons back, but when the
computer was turned off and then back on, they were gone again. Where are they, and how do we
get them back?
A. It sounds like you have been hit by one of Windows XP's 'wizards' - there is one named the
Desktop Cleanup Wizard that will remove unused (in last 60 days) icons from your desktop to a
folder it places on the desktop named "Unused Desktop Shortcuts". You can restore the icons by
opening that folder and dragging the desired icon back to the desktop. However, if in a fit of
cleanliness, you happened to remove the Unused Desktop Shortcuts, then those icons are gone.
You can read more about it at this Microsoft page:
http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/display_desktop_icons_remove.mspx
Q. Are there ways to take a snapshot of the system, so that if something like this happens, I can
get back to the way the machine was configured?
A. In Windows XP, clicking START / ALL PROGRAMS / ACCESSORIES / SYSTEM TOOLS
/ SYSTEM RESTORE will give you a utility that will copy your system registery and other
related information into a 'restore point.' When you get the screen, select the "radio button" for"Create a Restore Point." Later, if you need to come back, you will be given a list of restore
points that you can reload. It is a VERY good idea to do this immediately prior to installing any
hardware or software. The restore points are given the date and time as part of their name; you
may add other text to the name such as "prior to installing widget board"
Q. I have a machine that has gotten very slow. I have looked in MSCONFIG, and it lists all sorts
of things, but I don't know whether it is safe to block them. Any suggestions?
A. For those who may not be familiar with it, MSCONFIG is a utility that Microsoft has included
in Windows XP. It lets you see which programs are being launched from various places in your
system. To start MSCONFIG, click START / RUN /; then type MSCONFIG and click the OK
button. On the various pages of the program, it will list things being started via Startup, or as
Services. If you see something that your are unsure about, one way to check is to do a web search
using Google. More often then not, you will get a description of the program module and what it
does.
Q. There is some sort of functionality in some ATA drives that permits the whole drive to be
encrypted via hardware. The concern is that a hack might be able to remotely activate the
encryption and then extort ransom for the decryption key. What have you heard about this?
A. It has been commented upon in Ed Foster's Gripe Line (Infoworld) column and perhaps
elsewhere. Yes, there is a mechanism to encrypt these drives if the drive's controller board is so
equipped. And yes, there is a way to lock the capability in the disabled mode so that it can't be
activated without a password. There have yet to be any reported incidents of this happening, and
the speculation is that the hacker would have difficulty in collecting the extorted funds without
being caught.
Q. I have an older machine, a Compaq Presario, running Windows Me. It no longer boots. I
talked to Compaq support, and they say that there is a recovery image in a hidden partition that I
can use to restore the machine. Is this advisable?
A. It depends. Usually these restore the machine to an "as purchased" state, which means that any
data will be lost. If that's acceptable, then fine. If not then you might be better off installing
Windows XP as a new operating system, but be careful to tell it to NOT wipe out the drive. At
today's prices for hardware, though, it might not make economic sense to invest anything in a
machine of that age. Another alternative is to see if the drive can be accessed as a slave drive
from a working machine. This would require removing the drive from the old machine, possibly
changing the jumpers on the drive, and then installing it in a working machine long enough to
copy the data to one or more CDs. Lastly, there are recovery services, but be aware that they
typically charge on the order of $800 per drive to recover data.
Q. Do I need a firewall? And if so, do I need a hardware firewall? I have a broadband
connection, and am using a wireless router and computers with wireless connections.
A. Firewalls work in several ways. First, let's address a traditional wired network. Your router
has a firewall, but it is set up to only protect you from an external attack that tries to enter from
the internet side (which is known as the WAN, or Wide Area Network, side). It prevents the
establishment of un-invited connections. In the diagram, our pirate is blocked at the router.
However, it assumes that any connection that is originated from the inside (the LAN, or Local
Area Network, size) is legitimate. Suppose that somehow the pirate manages to get a program
installed on your computer by some mechanism. For example, it might be a program that you
download, not knowing that it is a "Trojan horse". This is represented by the upper computer in
the diagram. In that case, when the program runs, it initiates a connection from the LAN side of
the router, which is let through - so a connection could be made with the pirate and the machine
is at risk. A personal firewall in a PC, represented by the lower PC in the diagram will sense that
a program is trying to get to the internet, and pop-up an alert. You then may decide whether to
permit it or to block it.
Now, to address WiFi access. Suppose the upper PC is an attacker's computer and it connects to
your WiFi network. It is already within the protected area of the hardware firewall, so that
firewall does not protect you. However, even though the intruder's computer is able to establish a
connection with the internet, if the other PCs in your local area network have personal firewalls
installed, they would block access to the PC by other PCs within the LAN unless explicitly
permitted.
Lastly, when you set up the router and WiFi network, there are steps you should take to secure
the WiFi access. This includes establishing an encryption key to prevent eavesdropping, and after
renaming the access point, turning off the broadcast of the router's network name so that it is not
visible to WiFi devices scanning for an access point. You can have even stronger access security
if you make use of MAC filtering. Every network adapter card has an absolutely unique
identification number, called a MAC ID. You can put the MAC ID of devices that you will
permit to connect to your WiFi access point and only those devices will be allowed to connect.
To get the MAC address of a network card, run the IPCONFIG command from a DOS Command
window. (On older windows machines, run WINIPCFG).
Q. Which brings up another question - how close does an intruder have to be in able to connect to
my WiFi network?
A. As with so many other things, "It depends." First, the power ratings for various devices
varies some are more efficient than others. The 802.11g devices tend to have somewhat better
signal strength (for sending) and more sensitive receivers (for receiving) than 802.11b. Some
devices have speed and/or range boost capabilities. What is between the two devices also matters
greatly the radio signal doesn't like to go through a lot of walls and furniture (especially steel
desks and filing cabinets). Most vendors state that their devices are good for 100 feet, if
unobstructed. There can be interference from other devices as well. For example, many cordless
telephones make use of the 2.4GHz band - the same frequencies used by WiFi. It doesn't matter
if the telephone is in use, as the handsets are always in communication with the base
station even if they aren't being used for a call. Also, you should be aware that there are
directional antennas available that are able to get better signal strength in one direction at the
expense of others. A search on the net revealed an unofficial record of 82 miles across Great Salt
Lake. It was done by using modified DSS antennas. Now before everyone becomes paranoid and
checks out every car that stops in the street, be aware that hackers typically aren't interested in
home networks, and they generally don't need to glom onto a home network's broadband
connection.
Q. I have the opposite problem how do I get good signal from the other side of the house?
A. First, 802.11g will probably be better than 802.11b. Next, the location of your wireless access
point is important putting it next to your home office computer may not be the optimum
location for the rest of the house. Some of the members suggested that it would be better to use a
centrally-located, standalone access point device rather than a router with wireless capabilities.
True, this does imply that you need to run at least one wire from your router to the access point.
There are also devices called repeaters. They may be wireless, in which case "one side" listens
for the signal, and if it gets a signal, it re-transmits it out the "other side." So, this device could be
placed somewhere in the middle of the house. Netgear has devices which perform much the same
function, but they make use of the electrical wiring within your house as the connection medium
between the devices. You run a wired connection from your router to one of these devices, which
is plugged into a nearby wall socket. Then, at the other end of the house, you have the
complimentary device which has the WiFi antennas on it. Note that the signal on the house
wiring will be on the electric wires leaving the house and get as far as the nearest power
transformer. In many areas each house may have its own power transformer (it is a device about
the size of a trash can and is mounted at the top of a utility pole). Follow your service line from
your meter out to the utility pole, and see if there is a transformer on the other end. If there isn't,
then theoretically your neighbors would be able to see the signal provided that they have the
same type of transceiver.
