Gmailで返信ができません
２名の方にメールを返信しょうとすると
下記のようなメッセージが戻ってきて
送信することができません
どうすれば送れるようになるでしょうか？
This is the mail system at host smtp0.XXXXXX.or.jp.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to <postmaster>
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
The mail system
・・・・・・・・・・・・・・・・・・・・・・・
This is an automatically generated Delivery Status Notification
Delivery to the following recipient failed permanently:
XXXX@XXXX.net
Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: XXX0 XXX X.X0.0 Authentication required (state XX).
