My sons have identically-configured laptops running XP. We have a Linksys
WAG54G v2 wireless gateway which has worked fine until recently. Now neither
PC can connect wirelessly, though wired connections to the router work fine.

XP can see the network and attempts to connect to it automatically, but
fails - either with a long "waiting for the network" or "obtaining network
address". A visitor's PC had the same problem.

I have tried:
- rebooting the router
- disabling WPA-PSK security
- changing frequency, in case of interference
- disabling the firewalls on the PC's (Zonealarm)
- bringing the PC's into the same room as the router to ensure a strong
signal
- running the XP "repair connection" tool - just says it cannot connect and
to contact the network administrator (I guess that's me)
- setting a static IP for the PC's (normally use DHCP)
all to no avail.

I don't think any settings have changed or anything relevant is likely to
have been installed; I did install a dial-up network connection on the PC's
for use when away from home, but it isn't attempting to dial.

Any suggestions please?

Chris R