Sony never intended this adapter for PC use. It was strictly a "Sony device" accessory. The official driver package (usually labeled UWA-BR100_Driver_EU.zip or similar) only supports:
Sony has not released, and will not release, a Windows 8, 8.1, or 10 driver. Installing the Vista/7 driver on Windows 10 will fail or cause instability.
You’ve installed the driver, but the Wi-Fi is flaky, disconnects, or has low signal.
Step 1: Download the Correct Driver
Do not search blindly. Go to a trusted repository like MediaTek’s legacy driver page or a reliable hardware database. The driver you need is often labeled:
Ralink RT2870 USB Wireless LAN Card Driver for Windows 10 (64-bit) sony usb wireless lan adapter uwa-br100 driver windows 10
Note: As of 2024-2025, a reliable source is the “Microsoft Update Catalog.” Search for “Ralink RT2870” and download the latest CAB file.
Step 2: Extract the Driver Files
If you download a ZIP or CAB file, extract it to a folder on your desktop (e.g., C:\UWA_BR100_Driver).
Step 3: Open Device Manager
Step 4: Force the Driver Update
Step 5: Handle the Driver Signature Warning If Windows warns you about an unsigned driver:
Step 6: Reboot After installation, restart your computer. The adapter should now appear as “Ralink 802.11n Wireless LAN Card” without any errors. Sony never intended this adapter for PC use
Try Windows Update automatic driver:
Install official Sony driver (if available):
Use generic/chipset vendor drivers:
Use compatibility mode if installer targets older Windows:
Reboot and verify: