Cannot send email via smtp.live.com

When attempting to send email via smtp.live.com on port 587, the server simply disconnects after I send the ClientHello:

--------------------------------------------------------------------------------------------

-->220 BLU436-SMTP92.smtp.hotmail.com Microsoft ESMTP MAIL Service, Version  8.0.9200.16384 ready at  Sun, 6 Mar 2016 22 00 11 -0800
<--HELO sender.example.com   
-->250 BLU436-SMTP92.smtp.hotmail.com Hello [154.5.112.xxx]
<--STARTTLS
-->220 2.0.0 SMTP server ready
<--16 03 03 00 49
01 00 00 45 03 03 56 DB 73 00 17 FD 7C ED 60 1F
BB 99 84 EB 53 8E 3E 1A EC 69 23 A0 D1 90 7C 92
4D 25 09 C6 78 0F 00 00 06 00 2F 00 3C 00 3D 01
00 00 16 00 00 00 12 00 10 00 00 0D 73 6D 74 70
2E 6C 69 76 65 2E 63 6F 6D
OK Bytes sent: 78
OK Finished SENDING
FD_CLOSE 988
REMOTE: sckClosing
STATE: sckClosing
STATE: sckClosed
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This same code works just fine on Gmail, and worked with Live the last time I tested it in December. What has changed?

J.A. Coutts