SONY VAIO VGN-NR21Z DOESN'T SEE WIFI - Computers & Internet

Be sure that your wifi button is ON
Be sure that your wireless network is working
Check your wireless router settings
Check if you see any other wireless network available on your computer

Test connection, see if you pulled an IP address

1. Go to the Windows desktop
2. Select Start then Run
3. In the text box type: cmd (WIN98/SE type command)
   At the command prompt type: ipconfig

4. What does it read as the IP address?
* If it reads 192.168. something dot something then you are pulling
an IP address and are connected to the network. The problem is
software related, check your firewall, and wireless card configuration.
Also check any WPA or WEP encryption keys. Check with the respective
manufactures.
* If it reads 0.0.0.0 for the IP address you are not connected to the network.
* Check your connection configuration and the adaptor.
* Check with the respective manufactures.

STEP TWO/ Basic troubleshooting continued....Testing the adaptor

1. Go to Windows desktop
2. Select Start then Run
3. In the text box type: cmd (WIN98/SE type command)
A DOS window will open.
4. At the prompt type: ping 127.0.0.1 (reserved IP address for all adaptors)
5. Check the line that reads "packets sent = 4, Received = 4, Lost = 0

A. Zero is good, the adaptor is working. Again check the connection
configuration,and the adaptor configuration.
It may be a power issue especially with older or less expensive computers
or wireless cards.
* Check the antenna location, are you inside or outside, look for interference.
* Check with the respective manufactures.

B. If it reads all 4 packets lost, the adaptor is not functioning.
* Check and update the drivers, Contact the respective manufactures.
* If it shows any number of packets lost (you are dropping packets)
it is an adaptor or signal strength issue (generally form the laptop side,
not being able to reach back) especially with older or less expensive
computers or wireless cards.
* Update the drivers
* Check antenna location, or distance from the signal
* Contact the respective manufactures.