Toshiba Tecra 8200 and PCMCIA WLAN

Hello,

I have a Problem with my Toshiba Tecra 8200 and an PCMCIA WLAN Adapter. My
Operating System is Windows XP (with SP1), but I also tried Windows 2000
(with and without SP3) and Windows NT 4.
The Problem is, that I could not connect to an Access-Point. I think all
Settings should be ok ( WEP off, SSID any, Infrastructure Mode). The
distance to the Access-Point is only 1 meter (for trying).
The Installation of the WLAN-Card is ok, no error appears in the Hardware
Manager.
I also tried it with two different WLAN Cards (Allnet0192 and D-LINK G650).
With the D-Link Card I could find the access-point, but could not connect
to. If I tried both of the cards in an other Laptop (DELL, Windows XP)
everything works fine.

This drives me mad! I dont know what to do now. Has anybody any hint for me?

Greetings

Michael