15 Solutions When Username and Password Not Accepted for SMTP Gmail

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Encountering issues with SMTP Gmail login can be frustrating, especially when you're trying to send emails through an external application or service. If Gmail doesn't accept your username and password for SMTP authentication, here are 15 solutions to help you troubleshoot and resolve the problem.

1. Check Your Credentials

First and foremost, double-check your Gmail username and password. Ensure there are no typos or mistakes. Remember, your Gmail username is your full email address.

2. Enable Less Secure Apps

Gmail, by default, might block access from less secure apps. You can change this setting by visiting your Google Account security settings and allowing less secure apps to access your Gmail account.

3. Use App-Specific Passwords

If you have two-step verification enabled on your Google Account, you'll need to generate and use an app-specific password for SMTP authentication.

4. Check Your SMTP Settings

Ensure your SMTP settings are correct. For Gmail, the typical SMTP settings are: smtp.gmail.com as the server, port 465 (SSL required), or port 587 (TLS required).

5. Update Your Software

Make sure your email client or the software you're using to send emails via SMTP is up to date. Outdated software might not support the latest security protocols.

6. Firewall and Antivirus Settings

Check your firewall and antivirus settings to ensure they're not blocking SMTP connections. Sometimes, security software can mistakenly flag SMTP traffic as suspicious.

7. Gmail Account Status

Confirm that your Gmail account is active and hasn't been suspended or disabled due to suspicious activity.

8. IMAP Settings

Although IMAP is used for receiving emails, ensuring your IMAP settings are correct can sometimes resolve SMTP issues as well, as they share similar authentication methods.

9. Clear Cookies and Cache

If you're trying to access Gmail via a web browser, clearing cookies and cache might help resolve login issues.

10. Try Another Device or Network

Sometimes, the issue might be with your device or network configuration. Trying another device or connecting from a different network can help pinpoint the problem.

11. Check Gmail's Server Status

Gmail might be experiencing outages or maintenance. Checking Gmail's official status page or social media channels can provide insights into any service disruptions.

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12. Contact Gmail Support

If all else fails, contacting Gmail support directly might provide additional assistance, especially if there's a technical issue with your account.

13. Review Third-Party App Permissions

If you're using a third-party app to send emails, ensure it has the necessary permissions to access your Gmail account.

14. Two-Factor Authentication

If you have two-factor authentication enabled, make sure you're using the correct authentication method when prompted.

15. Reset Your Password

As a last resort, resetting your Gmail password might help resolve authentication issues, especially if your account has been compromised.

Remember, when dealing with SMTP Gmail authentication issues, patience and careful troubleshooting are key. By following these 15 solutions, you should be able to resolve most login problems and successfully send emails through your Gmail account.

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