It looks to be a restriction of your server as I can connect to office365 using those settings. It then fails on authentication
SERVER -> CLIENT: 220 AM6P194CA0013.outlook.office365.com Microsoft ESMTP MAIL Service ready at Sat, 9 Feb 2019 20:05:16 +0000
CLIENT -> SERVER: EHLO dcameron.me.uk
SERVER -> CLIENT: 250-AM6P194CA0013.outlook.office365.com Hello [77.72.0.162]250-SIZE 157286400250-PIPELINING250-DSN250-ENHANCEDSTATUSCODES250-STARTTLS250-8BITMIME250-BINARYMIME250-CHUNKING250 SMTPUTF8
CLIENT -> SERVER: STARTTLS
SERVER -> CLIENT: 220 2.0.0 SMTP server ready
CLIENT -> SERVER: EHLO dcameron.me.uk
SERVER -> CLIENT: 250-AM6P194CA0013.outlook.office365.com Hello [77.72.0.162]250-SIZE 157286400250-PIPELINING250-DSN250-ENHANCEDSTATUSCODES250-AUTH LOGIN XOAUTH2250-8BITMIME250-BINARYMIME250-CHUNKING250 SMTPUTF8
CLIENT -> SERVER: AUTH LOGIN
SERVER -> CLIENT: 334 VXNlcm5hbWU6
CLIENT -> SERVER: bmFtZUBkb21haW4ub3Jn
SERVER -> CLIENT: 334 UGFzc3dvcmQ6
CLIENT -> SERVER: cGFzc3dvcmQ=
SERVER -> CLIENT:
SMTP ERROR: Password command failed:
SMTP Error: Could not authenticate.
CLIENT -> SERVER: QUIT
SERVER -> CLIENT: 535 5.7.3 Authentication unsuccessful [AM6P194CA0013.EURP194.PROD.OUTLOOK.COM]
SMTP ERROR: QUIT command failed: 535 5.7.3 Authentication unsuccessful [AM6P194CA0013.EURP194.PROD.OUTLOOK.COM]