I am assuming you have a switch with the WAP and your desktop connected to the switch, the notebook is wireless with a WPC54G.
2. Connect directly to the WAP with your desktop through a cable. Check the firmware release. The current version is 1.06, released by Linksys 2/25/2003. If your firmware is older than Version 1.06, go to the Linksys site and download, extract, and apply the updated firmware.
3. Go back to the configuration of the WAP. Disable DHCP. Reconnect the WAP to the switch or its original connection.
4. The WPC54G firmware has been revised several times. The current release is Version 1.21 released by Linksys on 6/24/2003. If your release is older than this, please update the drivers and Client Monitor utility.
The linksys ftp site can be reached here: ftp://ftp.linksys.com/pub/network/
Power off the notebook. Power off the WAP. Power on the WAP, and when it appears stable, Power on the notebook.