I've been unable to send emails for the last 4 days using Thunderbird and xtra. (I can receive emails OK.)
The error message is...
"An error occurred while sending mail. The mail server responded: 5.7.1 You are not authorized to send as email@example.com"
I read on the Spark website..
" Investigations have shown that this is affecting customers on older email clients and upgrading to a more secure modern client resolves the issues. If you are experiencing these issues and are on an older email client we recommend upgrading to a more secure modern client."
I like Thunderbird. Can anyone suggest a good 'modern' replacement?