I made the change so that MailFrom is in smtpsend.
my @ok = $msg->smtpsend( Host => $full_host_name, MailFrom => $From, To => $To, Debug => 1 );

This did give a different set of debug messages as shown below.
I visited the bt site and found that I should enable SMTP authentication in my e-mail program.
I assumed that this meant my e-mail application which is Thunderbird 31.7.0. However, in spite of searching in Thunderbird and web sites I could not find out to do this.
Can anyone help?

Net::SMTP>>> Net::SMTP(2.31)
Net::SMTP>>> Net::Cmd(2.29)
Net::SMTP>>> Exporter(5.68)
Net::SMTP>>> IO::Socket::INET(1.33)
Net::SMTP>>> IO::Socket(1.37)
Net::SMTP>>> IO::Handle(1.34)
Net::SMTP=GLOB(0x27644f8)<<< 220 rgout05.bt.lon5.cpcloud.co.uk ESMTP Service ready
Net::SMTP=GLOB(0x27644f8)>>> EHLO localhost.localdomain
Net::SMTP=GLOB(0x27644f8)<<< 250-rgout05.bt.lon5.cpcloud.co.uk
Net::SMTP=GLOB(0x27644f8)<<< 250-DSN
Net::SMTP=GLOB(0x27644f8)<<< 250-8BITMIME
Net::SMTP=GLOB(0x27644f8)<<< 250-PIPELINING
Net::SMTP=GLOB(0x27644f8)<<< 250-AUTH=LOGIN
Net::SMTP=GLOB(0x27644f8)<<< 250-AUTH LOGIN PLAIN
Net::SMTP=GLOB(0x27644f8)<<< 250-DELIVERBY 300
Net::SMTP=GLOB(0x27644f8)<<< 250 SIZE 41943040
Net::SMTP=GLOB(0x27644f8)>>> MAIL FROM:<valid e-mail address>
Net::SMTP=GLOB(0x27644f8)<<< 530 authentication required - Your email could not be sent. To fix this you must make a simple change to your email clien t (known as SMTP authentication). For advice visit http://www.bt.com/smtp
Net::SMTP=GLOB(0x27644f8)>>> QUIT


In reply to Re^4: e-mail fails with address that is not a fully qualified domain by merrymonk
in thread e-mail fails with address that is not a fully qualified domain by merrymonk

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