Strange Wireless dependency issue?

I've got a little problem with my wireless network, the laptops in the house (typically 2) will connect to the network but cannot access the internet unless the other laptop is turned on? it seems a bit of a weird issue as if theyre dependent on one another, im running an apple powerbook G4 and my girlfriend has an XP HP laptop, the router is a G+ MIMO i think, any help would be appreciated. Thanks

You sure one isn't somehow bridging a connection to the other via some sort of weird connection sharing? It's kinda weird that neither will connect unless the other is there.

Thats what i thought might have been happening but i dont know how i could have done that in the first place!, im connected to the router not the other laptop, right this moment im online without the other laptop being on! but most of the time i can't connect, well it finds the network i type in the password but it connects for a second and then disconnects itself. Any ideas?

It's working with the other off... but usually doesn't? So you need to figure out what is actually going on here one computer at a time.

So connect the one that will connect by itself.. browse the web a bit then shut it down and turn the other one on and connect.

You need to try and isololate which one is having the problem.

If you find one that absolutely will not connect by itself, you need to stop there and work on getting that one to connect by itself.

The first thing I would do is temporarily turn off the wireless security and see if it connects. If it does, then you can start playing around with security settings.

Also, if your wireless router has SuperG mode or some funky speed enhancer stuff, turn that off. Basically you want to turn off all the Bells and whistles of the router and then start turning things back on and see which setting breaks either the Apple or the HP. Leave the DHCP on though. If the router has any error logging, it might give you an indication as to what's happening.

its not one of the computers that has it, if one of the two are off then the wifi will sometimes not connect, ive narrowed the problem down to the router, which is not always giving IP adresses to the laptops which means they cant connect. It gives an IP adress which will not let it connect to the internet?