Microsoft Security Essentials 4.10.209.0 Download - Free Antivirus for Windows Vista and 7 (and XP)

[Trisha Takanawa]

Need free antivirus for an older Windows PC? Microsoft Security Essentials is Microsoft's own free antivirus and anti-spyware program for Windows XP, Vista and Windows 7, and the forerunner of Windows Defender in Windows 8 and 10. This download has two versions: 4.10.209.0 for Vista and 7, and the older 4.4.304.0 for XP.

Download:

Download Microsoft Security Essentials 4.10.209.0

1. Extract the zip and open the folder for your Windows: Vista-7 or XP.
2. Run the installer for your system type: MSEInstall_4.10.209_x86.exe for 32-bit Vista or 7, MSEInstall_4.10.209_x64.exe for 64-bit, or mseinstall_4.4.304_x86.exe on XP.
3. Follow the wizard. Uninstall any other antivirus first, because two of them fight each other.

Tip: the installer doesn't carry virus definitions. The program downloads them itself, so connect to the internet once it's installed and let it update. Microsoft stopped providing definition updates for XP in July 2015, so on XP it's of little use now.

Update: Microsoft has since retired Security Essentials along with the systems it ran on, and it's gone from its download pages.