Troubleshooting
Wireless Networking
Connectivity
There could
you various reasons why a PC could not connect to a Wireless
network. Some of the possible reasons are:
1. Wireless
device in PC not installed or disabled.
2. Wireless
Router / Access point not configured
correctly or failure.
3. Wireless
device in PC not configured correctly
(SSID or Security).
4. Interference from other wireless devices.
For latest Microsoft Windows Vista Wireless Updates and Hot fixes, visit here.
Troubleshoot
Wireless network adapter in the PC:
Often it may
turn out a
disabled or not properly installed network adapter is the reason for a
connectivity issue. Your first step in troubleshooting network issues
should
start here.
This check
list should help you
resolve issues with your network adapter:
o Check if your
notebook has On/Off switch or a
special function key to enable Wireless network adapter.
o Verify from
Device Manager that Wireless card
drivers has been installed and working. If a
updated
version of driver available, download and install it.
o If
it’s a PCMCIA card, remove and reinsert while
Windows Vista is running. This should re-detect and install the drivers
needed.
o Verify the
Network adapter power setting is set to
100%. You can verify this from Power Output tab of Wireless networking
card
driver properties (Device Manager | Wireless networking
card properties | Power
Output tab).
Troubleshoot
the Router / Access point:
Most
routers have
lights that indicate specific network conditions. Your specific router
may have
different lights.
· The
Power light should always be
solidly on. If the power light is not on, check the power adapter or
try a new
power outlet.
· The
Test light should be on only when
the router is first turned on or if it is reset. If the Test light is
always
on, your router may have a mechanical problem.
· The
Internet Link light should be
solidly on if the router is connected to a LAN, DSL, or Cable modem.
The DSL or
Cable modem must be on for the Link light to be solid.
· The
WLAN or Wireless light should be
solidly on at all times. Even when there is no wireless devices
connected to
the router. The WLAN activity light should flash when there are packets
being
sent or received from any computer connected through the router.
· Reset the wireless
router by
removing the power from the router for 10-15 seconds if you identify
any issues
with Router.
For
troubleshooting
information specific to your router, see the manufacturer's web site or
the
documentation provided with the router.
Check
Security and Encryption Settings:
Confirm
that the
security and encryption settings required by Wireless networking card
in PC
matches the settings in Wireless Router. You can refer to the
documentation
provided with the Router for help in accessing Router interface. Most
wireless router settings can be accessed by typing the following URL in
the
Address bar of Internet Explorer: http://192.168.1.1
To modify the Security and Encryption settings for a Wireless networking adapter, refer to our Managing Wireless Networks section here.
Interference
from other devices:
Many
times the
performance of your wireless network can be affected by environmental
factors.
These factors will not always cause interference, but must be
considered at
some point during your wireless network troubleshooting.
· 2.4
GHz cordless phones
· Microwave
ovens
· Electrical
parameter fences
· Electrical
transformers near the router
· Security
systems
· Other
wireless network transmitters
near the router
Troubleshooting
Wireless
Connectivity issues with Windows
The
Connect To a Network wizard helps the user diagnose a problem
Windows
Network Diagnostics can provide
guidance to the user by gathering diagnostic information about the
network
environment. Some common wireless networking problems for which Windows
Network
Diagnostics can suggest solutions include:
· Receiving a
weak wireless signal.
· Having a
disabled wireless radio.
· Successfully
connecting to the wireless networking
but not receiving an IP address assignment.
· Typing the
incorrect security key.
· Using invalid
digital certificates for EAP-TLS
authentication.
· Experiencing
hardware or driver incompatibilities.
· Having
authentication failures because of
infrastructure failure, such as an offline authentication server.
The raw
information gathered by Windows
Network Diagnostics, the repair options provided to the user, and the
choices
made by the user are all recorded in the System Event Log to assist
administrators in troubleshooting if users are unable to resolve the
problem
themselves. For more information, see the “Improvements to
Event Logging”
section below.
Windows
Network Diagnostics - Screenshot
Network
and Sharing Center
The Windows
Vista Network and Sharing
Center, as shown in Figure below, provides a clear view of both wired
and
wireless network connections; a network map to show how the computer is
connected to the Internet; and links for managing, joining, creating,
or
troubleshooting wireless networks. Users can also browse network
resources by
starting the new Network window, which is available by clicking View computers and devices.
The Network
and
If a network
connection is not available,
such as a failed Internet connection (even if the wireless connection
is
functioning), the Network and Sharing Center detects this failure and
displays
it graphically on the abbreviated version of the network map, as shown
in
Figure below. Users can troubleshoot the problem simply by clicking the
failed
portion of the network map to launch Windows Network Diagnostics.
To open the
Network and
Networking
System Tray Icon
In Windows
Vista, a single icon in the
system tray represents connectivity through all network adapters,
allowing
users with both wired and wireless network adapters to quickly
determine
whether they are connected to a local network or the Internet. By
creating a
single icon for all connection types, users no longer need to examine
multiple
network adapters to determine whether they have network access.
The networking
icon has four states, which
Table 1 shows.
Table 1. Four States
of the Networking Icon
|
Icon |
Status |
Description |
|||
|
|
No connectivity |
Represented by
an icon with a red X, this state indicates that no network adapters are
connected to the local network. |
|||
|
|
Connectivity
problem |
Represented by
an icon with an exclamation point on a yellow triangle, this state
indicates that a connectivity problem exists. When this icon is
displayed, users can use Windows Network Diagnostics to help them
troubleshoot the problem. |
|||
|
|
Local
connectivity only |
Represented by
an icon without an X, a triangle, or a globe, this state indicates that
at least one network adapter is connected to the local network but
cannot reach the Internet. When a user is using a hot spot, this icon
often means that the user has connected to the wireless network but
needs to use browser-based registration or authentication to gain
Internet access. |
|||
|
|
Internet
connectivity |
Represented by
an icon with a globe, this state indicates that at least one network
adapter is connected to the local network and that Windows Vista can
reach the Internet. |
If the computer has multiple network connections that have different
levels of
connectivity (for example, both wired and wireless network adapters),
the tray
icon will only communicate the greatest level of connectivity. To
display the
status of individual networks, users can click the icon, as shown in
Figure below.
Hover
over the networking system tray icon to view the network
adapter status
Wireless
Diagnostics Event Logging
When Windows
Network Diagnostics runs, it
creates events containing the following information:
· The name of
the wireless network adapter and
whether it is a native Windows Vista driver or a legacy driver.
· A list of
visible wireless networks with the signal
strength, channel, and protocol (such as 802.11b or 802.11g) for each.
Additionally, the event shows whether each network is infrastructure or
ad hoc.
· The list of
preferred wireless networks and each
network’s configuration settings.
· The diagnostic
conclusions, such as, “The wireless
connection on this computer appears to be working correctly,”
“The Internet
connection on the wireless router or access point might not be working
correctly,” and “The computer has a low signal
strength from wireless
network name.”
· The repair
options offered to the user, such as,
“Try moving the computer to a different location, eliminating
any sources of
possible interference, and then try connecting to wireless
network name
again.”
· The repair
options chosen by the user and whether
the repair solved the problem.
Windows Vista
also logs all wireless connections in the Event Log, not
just if diagnostics have been invoked.
Later, you can
view these events by using
the Event Viewer tool, as shown in Figure below. You can use the Event
Viewer
tool to help you understand the network environment at the time the
problem
occurred, without needing to recreate the scenario (a situation that is
often
impossible when users are traveling). Additionally, you no longer have
to
explain the symptoms of the problem.
Event
Viewer Tool
Occasionally,
you might need to escalate a
wireless networking problem to Microsoft or another support specialist.
To
ensure these specialists have as much information as possible about the
problem
and the diagnostics process, Windows Vista creates detailed debug logs
separate
from the System events. As Figure below shows, you can access these
events in
Event Viewer by expanding Applications
and Services Logs,
expanding Microsoft,
expanding Windows,
expanding Diagnostics-Networking,
and then selecting Operational.
These detailed debugging logs are not required
to troubleshoot most networking problems, however.
Debug
logs in Event Viewer
Wireless
Diagnostics Tracing
You can use
Event Viewer to examine
information about wireless problems after the problem has occurred. If
you have
a recurring wireless problem, you can also use tracing to capture and
analyze
even more detailed wireless diagnostics information. Tracing provides
extremely
in-depth troubleshooting data, including extensive detail about the
system’s
state and events that occurred while tracing was active. While Event
Viewer
reveals enough information to troubleshoot most common problems,
tracing
provides sufficient information for even the most complex problems and
can be
useful to system administrators, driver developers, hardware
manufacturers, and
Microsoft.
As shown in
Figure below, administrators
can start wireless diagnostics tracing by using the Computer Management
tool.
Additionally, administrators can use the Netsh
tool to start tracing
from the command line or from a script.
Administrators
can start tracing
interactively
Starting
wireless diagnostics tracing
causes Windows Vista to collect detailed information about wireless
adapters,
Group Policy settings, Windows Network Diagnostics, and overall
operating
system performance. After tracing has completed (or when an
administrator stops
tracing), administrators can view the collected information in a
report, as
shown in Figure below.
The report
includes the following
information:
· Wireless
configuration, including allowed and
blocked wireless networks
· Current IP
configuration (including data provided
by the ipconfig /all
command)
· A list of all
connection attempts, and detailed
information about each step of the connection process
· A detailed
list of all Windows Network Diagnostics
events
· Wireless
certificate information
· Wireless
profiles and their locations
· Wireless
network adapter driver information
· Wireless
networking system files and versions
· Raw network
tracing information
· Computer make
and model
· Operating
system version
· A list of all
services, their current states, and
their process IDs