How can I solve the "Username and Password not accepted" or "EOF" error when sending a test email via SMTP?


Troubleshooting


EOF or Username and Password not accepted.

As a backup administrator, you may wish to use a “Custom SMTP Server” to send backup status reports. However, even after entering the correct information for the SMTP host, port, username and password, you might still run into a “Username and Password not accepted” error or an “EOF” error when clicking the “send a test email” link. Please try the troubleshooting solutions below:

EOF not accepted

For the Gmail SMTP server, please try one of the solutions listed below:

Solution 1

For the sake of security and privacy, we recommend that you create an App password to grant permissions to access your Google Account.

  1. Go to your Google Account.
  2. On the left navigation panel, click Security.
  3. Under “Signing in to Google”, select 2-Step Verification and follow the on-screen steps to enable it.

    If you don’t have this option, it may be because 2-Step Verification has not been set up in your domain. In that case, please contact your domain administrator to enable it or proceed with Solution 2.

  4. Under “Signing in to Google”, select App passwords.

  5. At the bottom, click Select app and choose “Mail”, then click Select device and choose the device you’re using. Finally, click GENERATE.

  6. Copy and paste the displayed password into the CubeBackup console and send a test email to verify whether all settings are correct.

Solution 2

You can also allow less secure app access.

  1. Go to your Google Account.
  2. On the left navigation panel, click Security.
  3. In the “Less secure app access” panel, click Turn on access.
  4. Switch on “Allow less secure apps”.
  5. Now you can go back to the CubeBackup console and send a test email to verify whether all settings are correct.

x509: certificate signed by unknow authority

CubeBackup will connect to your custom SMTP server using TLS. If you are using an internal SMTP server with a self-signed certificate, CubeBackup may recognize the connection as insecure and return the error message above and reture the error message below. certificate signed by unknown authority If you trust the SMTP server, you can modify the configuration file /db/config.json and change the value of “SmtpSkipVerifyTLS” to true. If your config.json file does not contain this field, you can simply add the following line.

"SmtpSkipVerifyTLS": true,

configure CubeBackup to skip verify TLS certificate