Add Defender Exclusions with PowerShell (Add-MpPreference)

Skip antivirus scanning for a build folder or a trusted process using the Defender module's Add-MpPreference.

WindowsdefenderadminpowershellMedium risk

Run Add-MpPreference -ExclusionPath <folder> or -ExclusionProcess <name> in an elevated PowerShell.

01Command

Command

$ Add-MpPreference -ExclusionPath 'D:\dev\build' ; Add-MpPreference -ExclusionProcess 'node.exe'

02What it does

Real-time scanning of huge build outputs (node_modules, obj/bin, Docker layers) is a classic cause of slow development machines, and exclusions are the documented remedy. Exclusions can be scoped by path, extension, or process name, and Get-MpPreference shows what is currently set. Each exclusion weakens protection — Microsoft recommends narrow, specific paths rather than whole drives, since malware in an excluded folder is invisible to Defender.

03Risk

RiskMedium risk

RequirementsRequires an elevated PowerShell session; Defender must be the active antivirus

!Warning: Every exclusion weakens your antivirus protection; exclude only specific trusted folders, never whole drives.

04Undo

Undo

$ Remove-MpPreference -ExclusionPath 'D:\dev\build' ; Remove-MpPreference -ExclusionProcess 'node.exe'

05Sources

Add-MpPreference (Defender module)
Microsoft Learn · vendor-doc · 2026-09-17
Evidence: Documents the Add-MpPreference cmdlet and its -ExclusionPath / -ExclusionProcess parameters.
Configure and validate exclusions for Microsoft Defender Antivirus scans
Microsoft Learn · vendor-doc · 2026-09-17
Evidence: Documents path, extension and process exclusions, and warns that exclusions create a gap in protection and should be as specific as possible.

Last verified: 2026-09-17 · Category: Security & Privacy

06Related solutions

Grep on Windows: Select-String

Windowssearchtextpowershell

Search inside text files and logs with regex, returning file, line number and match.

Low risk ✓ 2026-09-17

Zip Files with Compress-Archive

WindowsZip & Archivesarchivepowershell

Create or update a .zip from any files or folder contents straight from PowerShell.

Low risk ✓ 2026-09-17

Test a TCP port connection on Windows with Test-NetConnection

Windowsnetworktroubleshootingpowershell

A built-in PowerShell one-liner that answers 'is port 5432/3389/443 actually open through this network?' — no telnet client needed.

Low risk ✓ 2026-09-17