The recipient server is not responding. This issue is explicitly regarding the recipient incoming mail server.
Causes
Used up all your data transfer quota.
Fixes
Step 1: Contact Server Administration
There is not much that we can do, can try to contact the server administration for the recipient server, however using an alternative choice of method for contacting the recipient would be preferred solution.
Step 2: Send Message Until The Recipient Server Comes In A stable State
Send the message until the recipient server comes in a stable state and receives the mail, therefore this is a time-consuming process as this does not have fixed defined attempts.
- However, SMTP server has made this process automated. The sender server will try to send the mail again and again. Note that, the occasions the procedure proceeds thoroughly rely upon the design of the sender server.