Open Windows Settings > Default Apps. Scroll down to "Choose default protocols" and find "Magnet." Point it directly to your portable utorrent.exe path.
Version 2.2.1 was coded during the era of “netbooks” and 512MB RAM machines. It is written in highly optimized C++. On a modern fiber connection (1Gbps), this client can saturate your bandwidth without using more than 15MB of RAM. Modern Electron-based clients (like the new WebUI versions) often use 300MB+ for the same task. utorrent 2.2.1 portable
Ensure "Check for updates automatically" is unchecked to prevent it from overwriting itself with a newer version. Open Windows Settings > Default Apps
Set "Put new downloads in:" to a folder on your largest hard drive. Set "Move completed downloads to:" to an organized archive folder. "Append .!ut to incomplete files" so you know what is still downloading. It is written in highly optimized C++