using relay SMTP overseas

[#1]

My Dad is trying to use his laptop to send email from India.  I have tried to setup authentication with TLS on port 587 but it produces an error message.  All the Plusnet help pages seem to be from 2012 and show using port 25.
Is it possible to send email securely with relay.plus.net using authentication? 

[#2]

The Plusnet SMTP relays do not currently support use of SSL/TLS. Authentication needs to be used when not on a Plusnet connection (using either port 25 or port 587) but it can't be used with SSL/TLS.
Rather than exposing the account password an additional mailbox can be set up, eg called auth with its own password. Then use that for authentication with username as accountname+auth and the newly created password. for auth. There is no need to change the sender name/email address.

[#3]

Sending emails from when I worked overseas (Pakistan, Saudi Arabia, Cameroon) I often had port and other problems. I usually got a long term solution by getting the server details from the local ISP.