Solution: 535 5.7.3 authentication unsuccessful office 365 SMTP Error

For some reason Office 365 SMTP throws below error when trying to access via SMTP from other applications or services such as Gmail. Example error in Gmail: Secured connection using TLS (recommended) O Secured connection using SSL Authentication failed. Please check your username/password. Server returned an error: “334 VXNlcm5hbWU6 334 UGFzc3dvcmQ6 535 5.7.3 Authentication unsuccessful…

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