Using Classic Outlook on Windows for personal email, calendar, and contact management
A co-worker had this TPM error, which he believe began to occur after a Windows/Office update. He was unable to add an account with Multi Factor Authentication enabled to Outlook, but he was able to add an account that didn't require MFA. So we thought it might be related to Modern Authentication. We used the following KB article to force Outlook to use Modern Authentication, and he was able to add his account to Outlook.