If you’re seeing the message “use an authenticator app on this computer,” you’re being asked to verify your identity using a time-based code. This guide walks you through exactly how to do that on Windows, step by step.
What This Message Actually Means
When a website or app says “use an authenticator app on this computer,” it means two-factor authentication (2FA) is required. Instead of a text message, you prove it’s really you by entering a 6-digit code that refreshes every 30 seconds.
The good news: you don’t need your phone. You can run an authenticator app directly on your Windows PC.
Why Use an Authenticator App on Your Computer
Most people assume authenticator apps are phone-only. They’re not. Running one on your Windows computer is actually more convenient if you’re already working at your desk. No phone fumbling, no switching devices.
Benefits include faster login, no dependence on mobile signal, and synced codes if you use a cloud-based authenticator.
Best Authenticator Apps for Windows (2026)
| App | Free | Windows App | Cloud Sync | Works Offline |
|---|---|---|---|---|
| Authy | Yes | Yes (desktop) | Yes | Yes |
| Microsoft Authenticator | Yes | Via web only | Yes | Yes |
| WinAuth | Yes | Yes (standalone) | No | Yes |
| 2fast | Yes | Yes (Windows store) | No | Yes |
| Authenticator for Windows | Yes | Yes (store) | No | Yes |
Recommended for most users: Authy or 2fast. Both are easy to set up and work well on Windows without needing a phone.
How to Set Up an Authenticator App on This Computer (Windows)
Step 1: Download an Authenticator App
Go to the Microsoft Store or the official app website.
For Authy: Visit authy.com and download the Windows desktop app.
For 2fast: Open the Microsoft Store, search “2fast,” and install it. It’s lightweight and works fully offline.
Step 2: Open the App and Create an Account (if Required)
Authy requires a phone number for backup recovery. Enter your number, verify it, and you’re in.
2fast does not require an account. Just open it and start adding codes.
Step 3: Add Your Account to the Authenticator
Go to the website or service you want to protect (Gmail, GitHub, Discord, etc.). Find the 2FA or two-step verification section in your account security settings.
Choose “Authenticator app” as your method. The site will show you a QR code.
Since you’re on a computer and the QR code is on the same screen, you cannot scan it with a camera the normal way. Here is what to do instead:
Option A: Use the manual entry key
Most sites show a text code below the QR code. It looks like this: JBSWY3DPEHPK3PXP. Copy that code. In your authenticator app, choose “Add account manually” and paste it in.
Option B: Use a QR code scanner extension
Install a browser extension that can read QR codes from your screen. Extensions like “QR Code Reader” for Chrome or Edge can scan a QR code directly from your browser window.
Right-click the QR code image and use the extension to read it. The secret key gets passed to your authenticator automatically in some setups.
Option C: Use your phone to scan, then transfer
If you have Authy on both devices, the code syncs. Scan the QR with your phone first, then the code appears on your computer too.
Step 4: Enter the 6-Digit Code to Confirm
After adding the account, your authenticator app will display a 6-digit code. This code changes every 30 seconds.
Go back to the website and enter the code when prompted. This confirms everything is working correctly.
You’re done. From now on, every time you log in, you open your authenticator app on your computer, read the code, and type it in.
How to Use the Code Each Time You Log In
- Log into the website as usual with your username and password.
- When prompted for the 2FA code, open your authenticator app on Windows.
- Find the account in the list.
- Type the 6-digit code before it expires (you have 30 seconds).
- You’re in.
The code resets every 30 seconds. If it’s about to expire, wait for the new one. Entering an expired code will fail.
What to Do If the Code Isn’t Working
Wrong time on your PC: Authenticator codes are time-based. If your PC clock is off by even a minute, codes will fail. Fix this by going to Settings > Time and Language > Date and Time > Sync Now.
Wrong account selected: Double-check you’re copying the code for the right account in the app.
Code expired mid-entry: Wait for the next code and try again.
App not syncing: If you’re using Authy, make sure it’s connected to the internet for first-time setup.
How to Back Up Your Authenticator Codes
This is the most important thing most people skip. If you lose access to your authenticator, you can get locked out of your accounts permanently.
Authy: Automatically backs up to the cloud. Enable encrypted backups in settings.
2fast: Use the export feature to save your accounts as an encrypted file. Store this file somewhere safe, like an external drive or cloud storage.
Save your backup codes: Every major site (Google, GitHub, etc.) gives you one-time backup codes when you set up 2FA. Save these in a password manager or printed in a secure location. Learn more about managing 2FA recovery options at twofactorauth.org.
Setting Up Authenticator for Specific Services
Google Account
Go to myaccount.google.com > Security > 2-Step Verification > Authenticator app. Click Set up, choose your device type (even though you’re on PC), and use the manual key option to add it to your Windows authenticator app.
Microsoft Account
Go to account.microsoft.com > Security > Advanced security options > Two-step verification. Microsoft recommends its own Authenticator, but any TOTP app works. Use the “other authenticator app” option and copy the manual setup key.
GitHub
Go to Settings > Password and authentication > Two-factor authentication. Choose an authenticator app, then use the manual key shown on screen.
Discord
Go to User Settings > My Account > Enable Two-Factor Auth. Enter your Discord password, then scan or manually enter the key into your authenticator app.
Authenticator App vs SMS: Why App Wins
| Feature | Authenticator App | SMS Code |
|---|---|---|
| Works without cell signal | Yes | No |
| Can be SIM-swapped | No | Yes |
| Works offline | Yes | No |
| Speed | Instant | Depends on carrier |
| Security level | High | Medium |
SMS codes are vulnerable to SIM swapping attacks, where a hacker tricks your carrier into transferring your number. Authenticator apps don’t have this problem because the codes are generated locally on your device.
Moving Your Authenticator to a New Computer
If you get a new Windows PC, do this before wiping the old one:
Export your accounts from the authenticator app. In Authy, your accounts are already in the cloud, just log in on the new computer. In 2fast, use the export feature and transfer the backup file.
If you forget to do this, use your backup codes to regain access to each account, then set up the authenticator again from scratch.
Conclusion
Setting up an authenticator app on your Windows computer is straightforward once you know the steps. Download an app like Authy or 2fast, add your accounts using the manual key or QR scanner, and you’re protected with a strong second layer of security.
The most important things to remember: sync your PC clock, save your backup codes, and export your authenticator data before switching computers. Do those three things and you’ll never get locked out.
Two-factor authentication stops the vast majority of account takeover attacks. Five minutes of setup is worth it.
Frequently Asked Questions
Can I use Google Authenticator on Windows?
Google Authenticator does not have an official Windows desktop app. You can use it through an Android emulator, but it is easier to use Authy or 2fast instead. Both support the same TOTP standard and work natively on Windows.
What happens if I lose my authenticator app or computer?
Use the backup codes you saved when setting up 2FA. Every major service provides these. If you lost those too, contact the service’s account recovery support. This is why saving backup codes matters so much.
Is it safe to have the authenticator app on the same computer I log in from?
It is slightly less secure than using a separate device, but still far safer than no 2FA at all. The main risk is if your computer is fully compromised. For most users, using an authenticator on the same PC is a perfectly reasonable and practical choice.
What is a TOTP authenticator?
TOTP stands for Time-based One-Time Password. It is the standard used by all major authenticator apps. Every 30 seconds, the app generates a new 6-digit code using your secret key and the current time. The server does the same calculation and checks if they match.
Can I use multiple authenticator apps at the same time?
Yes. You can add the same account to multiple authenticator apps by using the same QR code or manual key during setup. This gives you a backup in case one app becomes unavailable. Just make sure both devices are secured.
