# smartscreen.exe

Windows Process: Microsoft Corporation

Also called smartscreen, windows smartscreen, windows defender smartscreen

Windows, System Component

Microsoft Defender SmartScreen. It checks reputation of downloads and sites so a newly signed unknown file can be blocked before you run it.

## What you need to know

This checks download reputation. MsMpEng.exe still scans the file bytes.

smartscreen.exe is SmartScreen. It asks Microsoft reputation services about a file or site. A block on an unsigned new tool is the feature. It is not Antimalware Service Executable.

- **Safe?**: Yes. It is reputation, not the AV engine

  **Why did it block my installer?**: Unknown reputation

  **Same as MsMpEng?**: No

Feex says

If SmartScreen warned and the file is a tiny unknown exe from a forum, I would treat the warning as the point. I would not disable SmartScreen to save two seconds.

## What is smartscreen.exe?

smartscreen.exe is Microsoft Defender SmartScreen. It evaluates reputation for browsers, Store, and files you run from Explorer.

## What does it do?

It can delay a first launch while it looks up a hash. MsMpEng.exe may still scan the same file. Two layers, two processes.

## Why is it running?

You downloaded something, opened a Mark-of-the-Web file, or Edge asked for a reputation check. A resident copy is normal on current Windows.

## Is it safe?

Usually safe

System32 and Microsoft is SmartScreen. A smartscreen.exe in a "disable Windows" toolkit is not.

A legitimate copy normally runs from:

`C:\Windows\System32\smartscreen.exe`

- Expected publisher: Microsoft Corporation
- Reputation, not the Defender file engine
- Mark of the Web files trigger it

## Can I end it?

Blocks will stop until it starts again

Ending SmartScreen skips reputation prompts until Windows starts it. That is a security gap. Use Windows Security if you need a permanent policy change.

## Can I remove it?

No

Do not delete smartscreen.exe. App reputation is a Windows Security setting, not an Explorer delete.

## Should it start with Windows?

Windows starts SmartScreen with the user session. It should stay available.

## Normal resource behavior

These are contextual labels, not universal averages.

- **CPU**: Short spike on first run of a new file

  **Memory**: Small

  **Disk**: Low

  **Network**: Reputation lookup

## File information

| Executable name        | smartscreen.exe                     |
| ---------------------- | ----------------------------------- |
| Common legitimate path | C:\Windows\System32\smartscreen.exe |
| Publisher              | Microsoft Corporation               |
| Signature expectation  | Signed by Microsoft Windows         |

## Common problems

### Unknown publisher every launch

Unblock the file properties if you trust the source, or keep the warning. Do not turn the feature off globally for one tool.

### Offline PC

Reputation cannot look up. SmartScreen may fail closed or skip. That is the network, not a broken exe.

## Troubleshooting

Diagnose before you change anything destructive.

### Read the exact SmartScreen page

More info > Run anyway is a one-file choice. Settings > App and browser control is the policy.

### Do not use a "disable SmartScreen" reg file from a forum

Those files are a favorite malware dropper.

## Technical details

Technical details

| Image name | smartscreen.exe      |
| ---------- | -------------------- |
| Role       | Defender SmartScreen |

## Related

These entities connect to this article. Type is shown on every link.

[MsMpEng.exe: Windows Process](https://feex.it/wiki/process/msmpeng.exe)[Windows Security: Application](https://feex.it/wiki/software/windows-security)[Windows Defender: Windows Service](https://feex.it/wiki/service/windows-defender)

## Sources and verification

Reviewed by Feex editorial. Last verified August 2026 Status: Feex Reviewed. [How we research](https://feex.it/wiki/research).

- [Microsoft Learn: SmartScreen ](https://learn.microsoft.com/windows/security/operating-system-security/virus-and-threat-protection/microsoft-defender-smartscreen)· Reputation checks
- [Microsoft Support: SmartScreen ](https://support.microsoft.com/windows/smartscreen)· User-facing blocks
- [Foxhole process map ](https://foxhole.feex.it/)· First-party samples on Windows PCs. Not a lab benchmark.

## Was this article useful?

A yes or no is enough. Pick a reason if you want, or add a short note.

Quick facts

The short identity of this page. Specs, sources, and the full story stay in the article.

- **Type**: Windows Process

  **Publisher**: Microsoft Corporation

  **Executable**: smartscreen.exe

  **Typical path**: C:\Windows\System32\smartscreen.exe

  **Mapped by Feex**: Seen on Windows PCs in Foxhole

Feex Reviewed: Last verified August 2026

---

Source: [Canonical Feex Wiki page](https://feex.it/wiki/process/smartscreen.exe/)

[Developer guide](https://feex.it/wiki/developers/) | [API policy](https://feex.it/developers/api-policy/) | [Agent guidance](https://feex.it/wiki/llms.txt)