The UWA-BR100 is old, slow, and a hassle. For ~$10–15, buy a modern USB Wi-Fi adapter with native Windows 10 support (e.g., TP-Link TL-WN725N, or any adapter with RTL8812BU chipset). It will work instantly and perform better.
Surprisingly, if you have a clean Windows 10 installation (version 1809 or earlier), plugging in the UWA-BR100 and running Windows Update might fetch a driver.
Note: This option may not appear on Windows 10 21H2 and newer.
No. Never pay for drivers. Any website charging for this driver is a scam. The drivers are free from Realtek or Microsoft Update Catalog.
If you have found an older Sony driver file (originally for Windows 7 or Vista), you can try this workaround:
Warning: Avoid shady "driver update" websites that bundle adware. Stick to trusted sources.
Hardware Overview:
Why Windows 10 doesn’t recognize it automatically: Windows 10 has a massive built-in driver library via Windows Update, but many legacy devices—especially those from consumer electronics brands like Sony (not a pure networking hardware maker)—were overlooked. The UWA-BR100 uses a Realtek chipset. Since Microsoft stopped bundling unsigned or legacy Realtek drivers after the Windows 10 Anniversary Update (version 1607), the adapter becomes an "Unknown USB device" or shows a yellow exclamation mark in Device Manager.
Good News: Because the chipset is standard Realtek, a generic Windows 10 compatible driver exists for free—just not from Sony.