Hi Kathymably,
What’s your account type? Exchange, POP or IMAP?
Would you mind providing a screenshot of the pop-up window? If you cannot put the screenshot here, you can upload it to OneDrive (https://onedrive.live.com/) and then share the link here.
What’s the detailed error message?
A common cause is the incorrect cache in Windows Credential manager. We can remove the corrupted credentials to check the results.
Please go to Control Panel > Credential Manager. Under Windows Credentials, locate the set of credentials that has Outlook in the name. Click the name to expand the set of credentials, and then click Remove from Vault.
If issue persists, we can also
create a new profile in case your personal settings are corrupted.
Any updates, please feel free to post back.
Regards,
Perry
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