By the end of this tutorial, you'll know how to generate an app password for Yahoo Mail, configure it in lemlist for secure email authentication, and troubleshoot common connection issues while maintaining optimal security settings.

Yahoo requires app-specific passwords for third-party applications like lemlist as a security measure, especially when you have Two-Factor Authentication (2FA) enabled. This additional authentication layer protects your account from unauthorized access while allowing you to send personalized email campaigns at scale. Users who properly configure app passwords typically see 99% connection reliability and avoid authentication errors that could pause campaigns mid-flow.

Before starting this tutorial, ensure you have:

Step 1: Log into Yahoo Mail Navigate to mail.yahoo.com and sign in with your Yahoo credentials. This is your starting point for accessing security settings where app passwords are managed.

Step 2: Open Account Security Click on your profile icon in the top-right corner and select Account Info. Yahoo prioritizes account security, so you'll be prompted to re-authenticate — enter your password again when prompted.

Step 3: Navigate to Security Settings In the left sidebar, click the Account Security tab. This centralized location manages all authentication methods including app passwords, making it easy to control which applications can access your account.

Step 4: Access App Password Management Scroll to the bottom of the Account Security page and click Manage App Passwords. This feature creates unique passwords for each third-party service, ensuring your main password stays protected.

💡 Tip: If you don't see this option, you may need to enable Two-Factor Authentication first — Yahoo often requires 2FA before allowing app passwords.

Step 5: Create a New App Password Click Select App and choose Other App from the dropdown menu. This option lets you create custom app passwords for services not pre-listed by Yahoo.

Step 6: Name Your App Connection Type "lemlist" as your custom app name and click Generate. Using a clear, identifiable name helps you manage multiple app passwords and quickly identify which services have access to your account.

Step 7: Copy Your Generated Password Yahoo displays a 16-character app password. Copy this immediately — you won't be able to view it again once you leave this screen. This password replaces your regular Yahoo password when connecting to lemlist.

⚠️ Important: Don't close this window until you've successfully connected to lemlist in the next phase.

Step 8: Access lemlist Email Settings In lemlist, click your profile icon (bottom-left corner) and select Settings → Sending Settings. This is where all email provider connections are managed.

Step 9: Add Yahoo as Email Provider Click Connect new email address and select Other email provider (Yahoo requires manual SMTP/IMAP configuration). Click Advanced settings to reveal configuration fields.

Step 10: Enter Connection Details Configure your Yahoo connection with these settings:

Step 11: Test and Save Connection Click Test Connection to verify settings, then Save once successful. lemlist will confirm the connection with a green checkmark, and your Yahoo account is now ready for campaigns.

Here's how Sarah, a B2B sales manager, uses her Yahoo-lemlist connection:

Example Workflow:

Try It Yourself Checklist:

Issue: "Authentication Failed" error in lemlist

Issue: Connection works but emails aren't sending

Issue: App password option not visible

Issue: Sporadic disconnections after initial setup

For persistent issues, see How can I resolve email connectivity issues on lemlist

Before launching your first campaign, verify your setup: