This error means that your Office 365 account does not have a mailbox for the email address you're trying to connect. For example, you may have an Office 365 account that you use for other products such as Word or Excel, but your email is hosted with a different email provider. You will need to choose the correct provider to connect your calendar or email.
HubSpot automatically connects to the wrong email
If you see that HubSpot is automatically connecting to the wrong email address, make sure you haven't opted to stay signed into your Office 365 account.
In the top right, click your profile picture, then select Sign out.
After logging out, navigate back to your HubSpot email integration settings, then follow the steps to connect your Office 365 inbox or calendar to HubSpot.
Unavailable - API access not enabled for mailbox
You'll see this error in your HubSpot account as OFFICE_ERROR_REST_API_NOT_ENABLED_FOR_COMPONENT_SHARED_MAILBOX. This error can be caused in one of two ways:
This error can be an indication that you're in the process of being migrated from an outlook.com/hotmail or other service to an Office 365 account. This migration can take some time, and this error will appear if you attempt to connect while migrating.
This error can also mean that your domain is using a hybrid on-premises exchange and an Office 365 setup. This means that you have an Office 365 account, but you do not have a mailbox managed by Microsoft directly. As a result, HubSpot cannot access the REST API for your mailbox. HubSpot requires REST API to connect to an Office 365 account. One way to verify that your email inbox isn't hosted on Office 365 is to look up your email domain in MX Toolbox, which is an external site that displays MX records. For example, this MX lookup shows that the domain sidekick.engineering is hosted by Office 365, but this MX lookup for mac.com shows no known email provider.
If you see this error, you will need to connect using a different email provider. For example, you could connect via IMAP or via Exchange if you're running an Exchange server.
Connected Office 365 inbox displays as outlook_[string_of_characters]@outlook.com
You may see outlook_[string_of_characters]@outlook.com display instead of your email address when you connect an Office 365 inbox. This is because HubSpot does not support using a non Microsoft domain primary alias. This can causes issues with sending or syncing your emails from your connected inbox. Learn more about this issue and Microsoft's recommended solution.
Interaction required error
If you see an "Interaction required" error when connecting your Office 365 inbox, it means your user needs access to the HubSpot Sales application in Azure AD. You may need to work with your email administrator to get access. Learn more assigning users to an application in Azure AD.
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