BUFFALO WI-U3-866D Wireless LAN Adapter driver

Hardware ID USB\VID_0411&PID_025D

Vendor: BUFFALO INC. (VID 0411)
Device: WI-U3-866D Wireless LAN Adapter (PID 025D)
Bus: USB
Drivers: 6
Windows: Windows XPWindows VistaWindows 7Windows 8Windows 8.1Windows 10Windows 11

Recommended driver

Realtek Wi-Fi Driver (RTL8188EU, AC-1200, AC1200, AC1750, AC1900 and more)

Version 1030.52.1216.2025 · Jan 9, 2026 · Windows 10, 11 · 64-bit

All drivers for VID_0411&PID_025D

Driver	Version	Date	Windows	Bits
Realtek Wi-Fi Driver (RTL8188EU, AC-1200, AC1200, AC1750, AC1900 and more)	1030.52.1216.2025	Jan 9, 2026	Windows 10, 11	64-bit
Realtek WiFi USB Adapter Drivers	1030.45.0422.2022	May 6, 2022	Windows 10	32-bit & 64-bit
Realtek RTL USB Wireless LAN 802.11n Adapter Driver	1027.4.0912.2016	Sep 29, 2016	Windows 7–10	32-bit & 64-bit
Mercusys MW300UM Wireless Mini USB Adapter Driver	V3, 1030.2.0731.2015	Oct 29, 2015	Windows XP–10	32-bit & 64-bit
Realtek RTL USB Wireless LAN 802.11n Adapter Driver	1027.4.1120.2014	Feb 16, 2015	Windows XP–8.1	32-bit & 64-bit
USB WiFi 802.11n Realtek Drivers	1026.13.0625.2014	Jul 30, 2014	Windows XP–8.1	32-bit & 64-bit

Is this your device?

Press Win + X and open Device Manager.
Right-click the device (often listed under Other devices with a yellow sign) → Properties → Details.
Select Hardware Ids in the list. If the first line starts with USB\VID_0411&PID_025D, the drivers above are for your device.

More about hardware IDs · Fix common device errors

Other BUFFALO devices with drivers