When you get a 0x800-type error in Outlook, it usually means Outlook is having trouble connecting to or communicating with your mail server. You can search for the specific error code in the Microsoft Support database (http://support.microsoft.com) for more information.

Some common causes include:

Incorrect SMTP authentication or security settings

Check that your SMTP authentication, port, and encryption settings match the settings provided by us.

Your ISP or network interfering with SMTP connections

Try changing the SMTP port to 587 or using your ISP’s SMTP server details.

A damaged Outlook account or profile

Try repairing the account or creating a new Outlook profile.

The hosting package and/or domain name have only been created in the last few hours

Allow some time for DNS to propagate, up to twenty four hours.

Your firewall is blocking your mail client

Check whether your firewall or antivirus software is preventing Outlook from connecting to the mail server.

No SPF and DKIM records set inside the DNS zone, or they might be outdated/correct

Microsoft may check a domain’s DNS records during Outlook setup and use SPF and DKIM as indicators that the domain is properly configured for legitimate email. If these records haven’t propagated yet or are incorrect, the setup may fail with a connection error.