Define the maximum size of downloaded files and attachments to be scanned

This policy setting defines the maximum size (in kilobytes) of downloaded files and attachments that will be scanned.

If you enable this setting, downloaded files and attachments smaller than the size specified will be scanned.

If you disable or do not configure this setting, a default size will be applied.

Supported on: At least Windows Server 2012, Windows 8 or Windows RT
Define the maximum size of downloaded files and attachments to be scanned

Registry HiveHKEY_LOCAL_MACHINE
Registry PathSoftware\Policies\Microsoft\Windows Defender\Real-Time Protection
Value NameIOAVMaxSize
Value TypeREG_DWORD
Default Value20480
Min Value0
Max Value10000000

windowsdefender.admx

Administrative Templates (Computers)

Administrative Templates (Users)