E6400 w/ 5100 AGN won't recognize router

for some reason, my sister's E6400 with the Intel 5100 AGN wifi card won't recognize and/or connect to our home wifi network anymore. my m15x (with the Intel 5300 AGN) and my iPhone have no problems whatsoever establishing connections. i have updated the firmware on the router and the card's driver, to no avail. any suggestions on solving this problem?

 

Please define "can't connect". What error do you get? Limited, can't see the signal, can't connect at all?

Does it work on other wireless network?
If so, then execute a Wireless repair connection (Vista and Win7 only), and see if it works after that once you followed the wizard. Else, it could be your router configuration. See the manual of your router or view teh support section of your router, or call them for help.

If you can't connect to any wireless, then the wireless card might have a driver related issue. Uninstall your wireless software (if any) and drivers, restart your computer, and install the latest drivers. If that still doesn't work, contact Dell.

 

Does it list the router on the available networks and show a good signal strength? If not, check if there is any security applied to the router (as a minimum I use hiding the SSID).

If the router uses any security but your computer has forgotten the settings then you need to set up a manual connection.

John