Unable to connect to an Office 365 account
If you've tried the usual (double checking your password) and are still unable to connect, Microsoft may be deliberately locking down your account for security reasons.
We've seen this several times. This happens when your credentials are correct, you're not using two-factor authentication or any other modern authentication, yet Office 365 is rejecting login requests from BusyCal / BusyContacts as it believes you're connecting from an unknown location (in case you've recently been traveling) or an unknown / non-trusted network. The way to 'fix' this is to:
1) Open a browser and logon to www.outlook.com with these credentials first. Once you log in successfully, close the browser.
2) Launch the app and try and login again (you may need to remove the account and add it back in again from Preferences > Accounts > selecting your account, removing it and then adding it back in again).
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