Make sure that you're running the latest firmware version on the AP.
I've had quite a lot of issues with my D-Link 2100AP before I upgraded the firmware!
Ola peeps
Been using my D-Link DAP-1150 wireless AP up to now without any problems.
All of a sudden my laptop as well as my HTC Desire will not connect to it. My phone continually ask me for the network code.
My wife's Nokia 5800 XM connects to it without a hitch.
Just went into the router's control interface and the code is correct with no settings being changed in the last year +
I unplugged it yesterday and plugged it back in, to no avail.
I dont want to hard reset as these AP's are crap difficult to configure.
Truevision | Visual Communication
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Make sure that you're running the latest firmware version on the AP.
I've had quite a lot of issues with my D-Link 2100AP before I upgraded the firmware!
i7 940 | Corsair 6GB DDR3 1600 + AX850W | Asus P6T Deluxe v2 + Xonar DX | 2x MSI Cyclone GTX 460 OC 1GB | CM 692 Advanced
Dell 3008WFP | Logitech MX500 + K350 | Sennheiser HD555
Thing is that this AP has never had a problem in the year+ that Ive had it
Truevision | Visual Communication
www.truevision.co.za Update Soon!
www.truevisionwebdesign.com Soon!
ok restarted my HTC and its on the wireless now... laptop still wont budge
Truevision | Visual Communication
www.truevision.co.za Update Soon!
www.truevisionwebdesign.com Soon!
Did your wireless get hit by lightning?
First thing is to make sure the laptops wireless is still working though, can you detect any other networks?
Or connect to any other AP's?
Maybe something on the laptop changed with a windows update or something?

Doesn't have to be lightning. Just a power surge. Screws them up good and solid. I would just reset the thing and reconfigure, rather than chipping away on the surface.
A power surge could damage it, but the fact that the phones work fine on it means the AP could be alright and there may be something wrong with the laptop, some models have a physical wireless switch on the side which may have been bumped or moved, also worth checking.
Uninstall the WLAN card on the lappie and get the latest drivers off the web then point the device management driver install to that folder. Ignore all currently installed drivers.
Maybe get a spare WLAN card to test.

@Jude: that's a good point, I guess one confirms the other. Something else to try is to go to Open Network and Sharing Centre > Change Wireless Settings or something like that. Delete all the wireless profiles you have and make sure you only have one. Maybe you had more than one with the settings being different, and then the wrong one became active.
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