FAQ

Quantum-safe encryption uses algorithms designed to resist attacks from both classical and quantum computers. All QNSQY tiers use hybrid ML-KEM + X25519 key encapsulation with AES-256-GCM authenticated encryption. Free tier uses ML-KEM-768, while Pro and Enterprise can select ML-KEM-1024 for maximum security. Enterprise adds ML-DSA digital signatures. All post-quantum algorithms were standardized by NIST in August 2024.

ZIP encryption has several weaknesses: (1) Older ZIP uses ZipCrypto, which is cryptographically broken and can be cracked in minutes. (2) Modern ZIP uses AES, but with weak key derivation (PBKDF2) that's vulnerable to GPU-accelerated brute force. (3) Neither is quantum-resistant. QNSQY uses Argon2id (memory-hard, GPU-resistant), hybrid ML-KEM + X25519 key exchange, and AES-256-GCM encryption on all tiers. For files that need to stay secure for decades, ZIP encryption is inadequate.

For quantum resistance, yes. GPG and 7-Zip use traditional cryptography (RSA, ECDH, AES with PBKDF2) that quantum computers will eventually break. QNSQY specifically addresses this threat with NIST-approved post-quantum algorithms. Additionally, QNSQY uses Argon2id for key derivation, which is more resistant to brute-force attacks than the older algorithms used by GPG (S2K) and 7-Zip (PBKDF2). If you need files to stay encrypted for decades, QNSQY is the better choice.

Estimates vary, but most experts believe cryptographically relevant quantum computers (CRQCs) could arrive within 10-20 years. However, the threat is already real due to "harvest now, decrypt later" attacks. Adversaries are collecting encrypted data today, waiting to decrypt it when quantum computers become available. If your data needs to stay confidential for more than 10 years, you should be using post-quantum encryption now.

Yes, completely. QNSQY has zero network capability by design. All encryption and decryption happens locally on your device. No internet connection is required, no data is sent anywhere, and no telemetry is collected. This air-gapped design ensures your files never leave your control.

Your files cannot be recovered. This is by design. QNSQY uses zero-knowledge architecture — we never see your password and have no way to recover encrypted files. We recommend keeping secure backups of critical passwords using a reputable password manager. Enterprise users have optional key escrow features for organizational recovery scenarios.

No. We have no access to your files, your password, or your encryption keys. Everything happens locally on your device. There is no server, no cloud storage, and no "master key." This is a fundamental security feature, not a limitation. If we could recover your files, so could anyone who compromised our systems.

Independent security audits are planned and will be published when completed. In the meantime, we use only public, peer-reviewed cryptographic standards that have been extensively analyzed by the security community: Argon2id (RFC 9106), AES-256-GCM (NIST SP 800-38D), ML-KEM (NIST FIPS 203), ML-DSA (NIST FIPS 204), and BLAKE3. We welcome security researchers to examine our implementation.

This is why NIST selected multiple algorithms. ML-KEM-1024 (based on the CRYSTALS-Kyber family) has been extensively analyzed since 2017 and is considered very strong. However, if a weakness were discovered, we would update to alternative algorithms. NIST has also standardized SLH-DSA (hash-based signatures) as a backup option. The modular design of QNSQY allows algorithm updates without changing the overall architecture.

The source code is proprietary. However, all cryptographic algorithms used are public standards with multiple independent implementations. You can verify our security claims by examining the NIST FIPS publications (203, 204, 205), the Argon2 RFC (9106), and other relevant specifications. We believe in "open standards, not necessarily open source" — the security comes from the algorithms, not obscurity.

Contact security@quantumsequrity.com with details of the vulnerability. We take responsible disclosure seriously and will work with you to address issues. Please allow us reasonable time to investigate and fix issues before public disclosure. We do not have a formal bug bounty program, but we acknowledge security researchers who help improve our products.

Free tier: up to 1 GB per file. Pro tier: up to 10 GB per file with streaming encryption (low memory usage). Enterprise tier: unlimited file size. The Pro and Enterprise tiers use streaming encryption, which processes files in chunks without loading the entire file into memory.

Windows 10/11 (64-bit), macOS 11.0+ (Big Sur and later, both Intel and Apple Silicon), and Linux (glibc 2.31+, including Ubuntu 20.04+, Fedora 32+, Debian 11+). Both x64 and ARM64 architectures are supported. Additional platforms (FreeBSD, mobile) are planned.

QNSQY encrypts individual files. To encrypt a folder, first archive it (using tar, zip without encryption, or similar), then encrypt the archive. For example: tar -cf folder.tar myfolder/ && qnsqy-free encrypt -i folder.tar. This gives you a single encrypted file containing your entire folder structure.

Yes! QNSQY includes both a graphical interface (GUI) and command-line interface (CLI). The GUI provides easy drag-and-drop encryption for everyday use, while the CLI is ideal for automation and scripting. Both interfaces provide the same encryption capabilities and are included in every download.

Yes. The encrypted file format (.qs) is platform-independent. Files encrypted on any operating system can be decrypted on any other supported operating system. The same applies across tiers — files are cross-compatible regardless of which tier created them.

Purchase a Pro license, download the qnsqy-pro binary, and install it alongside or in place of qnsqy-free. Your existing encrypted files will continue to work — the file format is identical across all tiers. You'll immediately gain access to Pro features like larger file sizes, streaming encryption, digital signatures, and key management.

Yes. Pay once, use forever. No subscriptions, no recurring fees, no "maintenance" charges. You receive lifetime access to the version you purchased, plus all updates within your major version. We believe security software shouldn't hold your files hostage with ongoing payments.

Yes. 30-day money-back guarantee for Pro licenses. If QNSQY doesn't meet your needs, contact us within 30 days for a full refund. No questions asked.

The Free tier is licensed for personal, non-commercial use only. For commercial use, business environments, or organizational deployment, please purchase Pro or Enterprise licenses. The encryption is identical — it's purely a licensing distinction.

Free: unlimited personal devices. Pro: licensed to a single user, installable on all devices that user personally owns and operates. Enterprise: licensed per-seat, with volume discounts available. Contact us for site licenses if you need organization-wide deployment.

The password you entered doesn't match the password used to encrypt the file. Check for typos, caps lock, or keyboard layout issues. Passwords are case-sensitive. If you've forgotten the password, the file cannot be recovered.

The encrypted file has been modified or corrupted since it was created. This could be due to incomplete file transfer, disk errors, or intentional tampering. The file cannot be decrypted. If you have a backup of the original encrypted file, try that instead.

The file exceeds your tier's size limit. Free: 1 GB. Pro: 10 GB. Enterprise: unlimited. Upgrade to a higher tier for larger files, or split the file into smaller parts before encrypting.

macOS may quarantine downloaded binaries. To clear the quarantine: xattr -d com.apple.quarantine /path/to/qnsqy-free. Alternatively, right-click the application and select "Open" to bypass Gatekeeper. We're working on Apple notarization for future releases.