Hi @David Hands
In order to better study this issue, please provide more details:
What is your email type (Microsoft 365/Gmail/IMAP/Other)?
Can you provide a screenshot of the specific error message? Please be careful to cover your personal privacy information.
Please understand that New Outlook is not yet fully designed, and some account types are not supported at this time. The following account types are supported by New Outlook:
Microsoft accounts such as an Outlook.com or Hotmail.com account, work or school accounts assigned to you by your organization’s admin, third-party accounts such as Gmail, Yahoo!, iCloud, and other third-party accounts connecting through IMAP.
If your account type is not currently supported, to quickly obtain account support, it is recommended that you could post the functions you expect and your sincere suggestions on the website dedicated to collecting feedback. We sincerely welcome your suggestions, and thanks for your understanding and support!
Hope this helps!
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