To resolve errors like error code 3 when attempting to send an email from BUSY, you can try the following troubleshooting steps:
1. Check your internet connection to ensure it is stable and working properly.
2. Verify that the email settings in BUSY are correct, including the SMTP server address, port number, and authentication details.
3. Disable any antivirus or firewall software temporarily, as they may be blocking the email connection.
4. Make sure that you have turn on 2 step verification and mention the app password in the email configuration.
5. Make sure that the email account you are using is active and accessible.
6. Restart the software and try sending the email again.
If the issue persists, it is recommended to contact BUSY customer support for further assistance.