Wireless LAN card shows yellow exclamation in Device Manager - ThinkPad
The wireless LAN will fail to operate and will show in Device Manager with a yellow exclamation. Reloading the driver and replacing the card does not resolve the problem.
Any ThinkPad systems running on Microsoft Windows XP or Vista maybe affected by this symptom.
Consult the Hardware Maintenance Manual for the specific system and make sure that the Mini-PCIe slot being used is for the Wireless LAN card, not for the Wireless WAN or other function slot. Placing the Wireless LAN card in the Wireless WAN card slot will result in the card being recognized, but unable to function (thus the yellow exclamation mark in Device Manager)