The WN121T causes many blue screens of death on Vista. A new driver was released that may fix some of the issues.
[WN121T Support Page]
Also WG111T 2.1 drivers released on the [WG111T support page].
The problem with this latest driver is that if you remote desktop to the machine using Vista then the network connection abruptly disconnects if Netgear manages your wireless connections. Everything works correctly if you let Vista manage the wireless connections.
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