Microsoft now requires authorization via the OAuth 2.0 protocol. If you're receiving notifications about using a less secure application or want to use the latest security protocol, try upgrading your Microsoft account to OAuth2.
- In a browser, ensure that you are logged out of all Microsoft accounts.
- Ensure that you are running Postbox 7.0.63 or higher.
- Within Postbox, navigate to Options | Settings > Privacy and then select the checkbox for "Accept cookies from sites."
- Navigate to Postbox Options | Settings > Security > Passwords > Saved Passwords and click the "Show Passwords" button. Take a screenshot of your passwords to keep as a backup. Then, remove your Microsoft-related passwords from the Password Manager and close the window.
- Navigate to Postbox Options | Settings > Accounts. Select the Microsoft account and ensure that you have the following settings:
- User Name — full email address
- Server Name — outlook.office365.com
- Type — IMAP
- Port — 993
- Security — SSL/TLS
- Password — OAuth2 (Microsoft)
- Navigate to Postbox Options | Settings > Accounts > [account list on the left] > Outgoing Servers and ensure that you have the following settings:
- User Name — full email address
- Server Name — smtp.office365.com
- Port — 587
- Security — STARTTLS (if this doesn't work for you, try SSL/TLS on port 465)
- Password — OAuth2 (Microsoft)
- Once complete, restart Postbox to authenticate your Microsoft account.