Windows 7: Fix Wireless Trouble

With the proliferation of wireless networks, it is becoming more and more likely that if you live in upwards of a fairly well a populated area, you are going to have problems with your wireless LAN.

Problems that are likely to include random wireless drops, undetectable or uncontactable wireless networks, data throughput problems, etc etc.

The question is - what can be done to try and get to the bottom of these problems?

Perhaps the best place to start is to run a single command line tool to find out as much information as we can about:

• Wireless adapter model
• Adapter card driver details
• Configured wireless LAN profile(s)
• Full details of wireless networks currently visible

As you can see, quite a lot of information from a single command!

Historically to get this level of information, you would need to look in several places (device manager, wireless networking info) and install 3rd party applications such as NetStumbler etc.

OK, so how do you get all this info from the single command?  Easy peasy.

1. Click Start (aka Windows Orb) and enter cmd into the text box and hit enter to open a command prompt
2. Into the command prompt window, enter the command:

netsh wlan show all >wireless.txt

3. This will run the command and pipe the output of the command into the file wireless.txt for easy reading
4. Still in the command prompt window, run

notepad wireless.txt

5. This will open the output from the "netsh wlan show all" command in notepad

With a bit of luck, you should now be looking at something that looks a bit like this:

=======================================================================
============================== SHOW DRIVERS ===========================
=======================================================================
Interface name: Wireless Network Connection

    Driver                    : Intel(R) PRO/Wireless 2200BG Network Connection
    Vendor                    : Intel Corporation
    Provider                  : Intel
    Date                      : Wed 19/12/2007
    Version                   : 9.0.4.39
    INF file                  : C:\Windows\INF\oem1.inf
    Files                     : 3 total
                                C:\Windows\system32\DRIVERS\w29n51.sys
                                C:\Windows\system32\Netw2c32.dll
                                C:\Windows\system32\Netw2r32.dll
    Type                      : Legacy Wi-Fi Driver
    Radio types supported     : 802.11g 802.11b
    FIPS 140-2 mode supported : No
    Hosted network supported  : No
    Authentication and cipher supported in infrastructure mode:
                                Open            None
                                Open            WEP
                                Shared          None
                                Shared          WEP
                                WPA-Enterprise  TKIP
                                WPA-Enterprise  CCMP
                                WPA-Personal    TKIP
                                WPA-Personal    CCMP
                                WPA2-Enterprise TKIP
                                WPA2-Enterprise CCMP
                                WPA2-Personal   TKIP
                                WPA2-Personal   CCMP
    Authentication and cipher supported in ad-hoc mode:
                                Open            WEP
                                Shared          WEP
                                Open            None
                                Shared          None
=======================================================================
============================= SHOW INTERFACES =========================
=======================================================================

etc etc etc!

Troubleshooting:

Channels in "SHOW NETWORKS MODE=BSSID" section
Find your wireless LAN and compare this to the channel details of the other wireless networks detailed in the results file.  If your wireless network is using the same channel as someone else's then change your wireless access point or router to use a different wireless channel.  

Signal strength in "SHOW NETWORKS MODE=BSSID" section
Yes I know the Windows 7 GUI gives you signal strength (and that's about all), but this method is more accurate.  Is the strength any good?  With a higher signal strength, is the wireless connection more stable?

These two are the most likely culprits when it comes to unstable wireless connections.

Some more advance troubleshooting includes: 

Driver in "SHOW DRIVERS" section
In my case:

    Driver                    : Intel(R) PRO/Wireless 2200BG Network Connection
    Vendor                    : Intel Corporation
    Provider                  : Intel
    Date                      : Wed 19/12/2007
    Version                   : 9.0.4.39

Armed with this info, I can hit Intel's website and see if there is a newer version driver available and update.

Alternatively, I could go to the Windows Update Catalogue and search for MS approved driver updates or hotfixes.  See here for how to use the catalogue.

Basic Rate and Other Rate in "SHOW NETWORKS MODE=BSSID" section
Try configuring your wireless card via device manager to run at one of the basic rates listed.  Does this make any difference?  Trial and error to see how fast you can go whilst remaining stable.

Conclusion
As we have seen, by running one simple command you can grab all sorts of valuable wireless information and  have a real good stab at fixing wireless networking woes.

If all else fails, then there is always Ethernet over power!

- Chris