Windows blocked the launcher: verify the publisher before adding exceptions

Scope and symptoms

First establish which security feature blocked which file. A familiar filename is not proof that a download is the publisher's original release.

Search fragments; wording and context vary:

Windows protected your PC
This app has been blocked

Source-supported context

Microsoft's Smart App Control and potentially unwanted application guidance describe different trust and blocking mechanisms. A blocked application is not automatically malicious, and it is not automatically a false positive either. V04-SMARTAPP V04-UNWANTED

Distinguish these cases

1. The file does not satisfy a reputation or signing policy; that is different from a specific malware detection.

2. A repackaged mirror or chat attachment cannot be matched to the publisher's release.

3. An organization controls device policy, or a security product quarantined one extracted component rather than the installer itself.

Suggested diagnostic sequence

This sequence is editorial guidance, not a diagnosis of your machine.

1. Record the security product, warning category and affected file. Identify whether the block concerns the installer or a component, and redact personal paths in shared reports.

2. Verify the version, digital signature and any published checksum at the original release source. Stop if identity information is inconsistent or missing in a suspicious way.

3. For a legitimate release that remains blocked, ask the publisher for a signed build or follow the security vendor's false-positive review process. Refer managed-device decisions to the administrator.

4. Obtain the confirmed release again and recheck the warning with protection still enabled. Preserve the publisher's or security vendor's response with the repair record.

Completion checks

The file has a traceable identity, the warning has been resolved through an appropriate process, and installation no longer loses quarantined components. Clicking an override is not a security audit.

Limits and cautions

This guide does not recommend disabling Defender or permanently excluding entire node or model directories. Custom nodes execute code; a successful launch does not prove they are safe.

Source review: 2026-09-22. No installation, GPU inference or user-environment repair was executed.

Original sources

• Microsoft: Smart App Control FAQ · 2026-09-22
• Microsoft: protect your PC from unwanted software · 2026-09-22

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