Name: TRENDnet TEW 421PC TEW 423PI 802.11g Wireless Cardbus PCI Adapter Driver
Author: TRENDnet

Question 1

Install fails or driver won’t load on modern Windows?

Accepted Answer

The older TRENDnet package may be unsigned or use a legacy installer. Run it as administrator, try Compatibility Mode for XP/Vista, or install the INF manually via Device Manager. If signature enforcement blocks it, use a supported older Windows VM.

Question 2

Adapter not detected (TEW-421PC CardBus / TEW-423PI PCI)?

Accepted Answer

Power off and reseat the card, confirm the CardBus/PCI controller is enabled in BIOS and Device Manager, and install motherboard/chipset drivers. Check for an “Unknown network controller”; if absent, try another slot or laptop.

Question 3

Version or utility conflicts?

Accepted Answer

Uninstall old TRENDnet drivers/utilities and other 802.11g adapters, remove hidden devices, reboot, then install one package. Avoid running the TRENDnet utility alongside Windows WLAN AutoConfig; use Device Manager rollback/update if versions conflict.