Delivery Status Notification (Failure) 收件箱

Mail Delivery Subsystem <mailer-daemon@gmail.com> 致 我
更多选项 9:21 (4分钟前)

This is an automatically generated Delivery Status Notification

Delivery to the following recipient failed permanently:

hunter@263.net

Technical details of permanent failure:
PERM_FAILURE: SMTP Error (state 9): 521 This User has too many concurrents, please try again later.