Mode 01
Standard
The protection veil is shown and the password field stays visible. Intensity is adjustable from 15 to 70 per cent.
Local access protection for Windows
Your computer stays protected once you step away.
ScreenShield21 protects access to your Windows PC as soon as you leave it, and gives you several safe ways to take back control: password, security key, paired phone, or recovery media.
Final signed RC1 · Official Windows download
Three ways to protect your screen
The mode decides what someone sitting down at your computer sees while you are away. You choose it from Home, before the next protection starts.
Mode 02
Hidden background
The screen is masked. This mode is opaque by design, so intensity is not adjustable.
Mode 03
Discreet
The password field is completely hidden. A shortcut you choose brings it back.
Several ways to take back control
Each method family is independent. The password remains the mandatory fallback method, whatever your configuration.
Password
Verified locally by the security engine. Always available, never removable.
Security key
A physical FIDO2 key whose possession is verified cryptographically.
Trusted device
A paired Android phone, with the permissions you grant it.
Recovery media
A USB key, SSD, or external drive prepared in advance and recognized when plugged in.
Your phone, two clearly separate uses
ScreenShield21 distinguishes browser access, with a duration approved on the PC, from the permanently paired installed Companion.
A — Temporary access
A browser is enough
The PC shows a temporary QR code. The phone opens it in its browser; the PC then approves the access duration.
- No mobile application required
- Several durations; 24 hours may be preselected
- The code expires on its own
- Closing the page does not revoke the approved pairing
B — Permanent trusted device
The Android Companion
After installation and a pairing approved on the PC, the phone becomes a permanent controller that keeps its link.
- Install ScreenShield21 Companion, then pair by QR
- See PC status, lock, request an unlock
- Local biometric confirmation if you enable it
- Permissions editable and revocable from the PC
Recovery is part of the product
Useful protection must account for losing an access method. ScreenShield21 prepares that path before you need it.
- Recovery media is created from a USB key, an SSD, or an external drive.
- Inserting valid media makes Recovery available without automatic unlocking. Its use remains explicit and locally verified.
- Temporary access can be granted to media for 1 h, 2 h, 8 h, 24 h, or until revoked.
- Closing the application requires authentication: no commercial state should trap a legitimate user.
Local first, and honest about its limits
Protection decisions are executed on your machine. The website takes part in no access decision.
The PC is the authority
Unlocking is decided locally. A paired phone asks; it never grants final access itself.
Nothing depends on this site
No unlock depends on screenshield21.com being available, or on a web account.
Not absolute protection
ScreenShield21 reduces specific local-access risks. It is not an antivirus, not a VPN, and not a guarantee against every attack.
Start with context
Understand first. Strengthen next.
The guides describe the signed RC1 behaviour, including what the product does not do.