Because Vista is no longer receiving security patches, a "legacy-friendly" antivirus is your only line of defense.
: One of the last major vendors still offering a version compatible with Vista. It uses cloud-based scanning to offload processing power. Windows Vista Antivirus Download
: A completely free, open-source engine. It does not have a real-time scanner (you must scan files manually), but it is incredibly lightweight and runs on almost anything. ⚠️ Critical Prerequisites Because Vista is no longer receiving security patches,
Before you can install any modern security tool, your Vista installation must be fully updated to its final possible state: : Essential for software compatibility. Windows Vista Antivirus Download
: Use MyPal or K-Meleon if you must go online; Chrome and Firefox abandoned Vista years ago.