先前发表文章和网上注册都用单位里的信箱，结果信箱成了各种广告的目的地。每天清理这些广告成为每日必做的功课。后来索性就不清理了。

结果没有几天，整个信箱都被塞满了。前些天发不出去信，昨天前天来了一封信说我的信箱被closed。这一下没有垃圾信件了。问题是正常的邮件也进不来了。

Your mailbox has exceeded one or more size limits set by your administrator.
Your mailbox size is 1005757 KB.
Mailbox size limits:
       You will receive a warning when your mailbox reaches 900000 KB.
       You cannot send mail when your mailbox reaches 950000 KB.
       You cannot send or receive mail when your mailbox reaches 1000000 KB.You may not be able to send or receive new mail until you reduce your mailbox size.
To make more space available, delete any items that you are no longer using or move them to your personal folder file (.pst).
Items in all of your mailbox folders including the Deleted Items and Sent Items folders count against your size limit.
You must empty the Deleted Items folder after deleting items or the space will not be freed.
See client Help for more information.

从这个通知看，好像如果我把这些垃圾邮件都清理了，这个信箱还能用，问题就是这些垃圾还会一如既往地来，我想问一下，哪些垃圾邮件现在应该被退回去了。哪些发送垃圾信件者发多久才能停止发送垃圾信件？否则，我清理了垃圾邮件，再来收垃圾信件，不是一点意义都没有么？