When you receive a 553 Error or a message saying “unable to verify address”, you need to set up SMTP Authentication in your email client.
Refer to the following articles to learn how to set up SMTP Authentication in your email client:
- Thunderbird
- Microsoft Outlook 2016
- Microsoft Outlook 2013
- Microsoft Outlook 2016 for Mac
- On Android Devices
- On iOS Devices
For further assistance, please open a support ticket from your HostPapa Dashboard. Follow this link to learn how.