The error you're encountering, "535-5.7.8 Username and Password not accepted," indicates an authentication issue with the Google SMTP server. This often occurs due to one or more of the following reasons:

1. Incorrect Credentials: The username or password entered might be incorrect.
2. Less Secure App Access: Google blocks access from less secure apps by default.
3. 2-Step Verification: If 2-step verification is enabled, you'll need to use an app-specific password.
4. CAPTCHA: Sometimes, Google blocks login attempts from new locations or devices.

Here's a step-by-step guide to resolve the issue:

1. Verify Credentials

Ensure that the username and password are correct. The username should be your full email address (e.g., yourname@gmail.com).

2. Enable Less Secure Apps

Google blocks sign-ins from apps or devices that do not use modern security standards. You can allow less secure apps to access your account by following these steps:

• Go to your Google Account.
• Select Security.
• Under "Less secure app access", turn on access.

Alternatively, you can use an app password if 2-step verification is enabled.

3. Use an App Password

If you have 2-step verification enabled, you must generate an app-specific password:

• Go to your Google Account.
• Select Security.
• Under "Signing in to Google", select App passwords.
• Generate an app password and use it instead of your regular password.

4. Clear CAPTCHA

To unlock CAPTCHA and allow access from new devices or applications:

• Visit https://accounts.google.com/DisplayUnlockCaptcha and follow the instructions.

5. Update Service Center Configuration

Ensure your email configuration in Service Center is set correctly:

• SMTP Server: smtp.gmail.com
• SMTP Port: 587 (for TLS) or 465 (for SSL)
• Use TLS/SSL: Enable TLS or SSL depending on the port you use
• Username: Your full Gmail address
• Password: Your Gmail password or app-specific password
• From Address: Your email address

Hi Carolina,

Can you please check and white Space in start or end of email configuration username and password filed.

Thanks

CV

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