Wireless problems, including Network Key disappears

I'm running a network in my two college kids' (Kid "A" and Kid "B") new apartment. I'm trying to set up their wireless network and having some problems that I hope you can help me with.

D-Link 524 router is set up Shared, WEP, Network Key programmed. IP address assigned by ISP (I'm pretty sure these are the settings).

Kid B: Toshiba laptop w/Vista OS. When I moved her into the new apartment I set her up to connect wireless via the D-Link 524 router, no problem. Pretty much rock solid.

Kid A: Toshiba w/Media Center Pro XP OS. She used this same D-link 524 router last semester in her old dorm room with no real problems. BUT... Now... the problem. Kid A's laptop see's the network router. When I tell it to connect, it tries and tries, then the little utility window goes away. The wireless icon in the trey at bottom right shows with and "X" (not connected) but it is connected. If I open Show Available Networks, it still indicates not connected, but the button at the bottom of the available network window shows "Disconnect" (normally, it would show "Connect" if I was not connected). And I can open a IE 7 and surf the internet, no problem. However, in 10 or 20 minutes I will get a little pop up from the wireless icon in the trey that says "Wireless Networks Available, and at that point, my internet connection is actually killed (browser stays open, but I can't move to another website or page.

At that point I look at the Network Connections Properties and I will find that the Network Key has now disappeared (that area is blank)! I can re-enter the Network Key and then I can again "connect" (even though it appears that I'm not connected, as I discussed above), and continue to surf.

Kid B laptop does not suffer any problem during this entire time/episode I have just described.

Please forgive my length on this, I hope it's not to convoluted to follow. To summarize, basically, on Kid A laptop, it indicates that I'm not connected via wireless, but in reality I am and can surf for a short while. Soon, the wireless (utility?) will tell me that wireless networks are now available, knocking Kid A laptop of the router and usually wiping away the Network key, which I can then go in and re-enter, and get back on the air.

I'm no network tech, far from it, but I have set up 4 or 5 networks with little or no problem. This one has me stumped.

Please read and help if you can.

Thanks everyone!

 

right click MY NETWORK PLACES, choose PROPERTIES
right click your wireless network connection, choose properties
choose the wireless networks tab

I don't recall the button's name on the bottom, but it might be something like MANAGE WIRELESS CONNECTIONS

click it and you will see a list of every wireless connection you connect to....select each and hit the delete button....get rid of them all

this ill delete all connections and stored settings, including passwords

Now, reconnect to the network and see if things stick this time

(I suspect a corrupt wireless connection)

 

Thanks very much for the reply. I'm headed back over there this week and will give it a try.