To see if it worked, open Windows Security → Virus & threat protection → Protection updates and check the "Last updated" timestamp. Manual install of Microsoft Defender Antivirus update
Depending on your system, you’ll need to choose the correct version: For most modern Windows 10 and 11 PCs. 32-bit: For older hardware or specific tablet versions. ARM: For Surface Pro X or similar ARM-based laptops. windows defender definitions update download
Here is everything you need to know about getting the latest and installing it properly. 1. Where to Download Official Updates To see if it worked, open Windows Security