What are the quota limits on the Exchange server?
The server limits are set as follows: Warning = 180 MB , Can’t Send = 200 MB, Can’t Send or Receive = 233 MB If your quota exceeds 180 MB , you will get a warning message every night alerting you. If your quota exceeds 200 MB, you will no longer be able to send e-mail messages or calendar appointments. If your quota exceeds 233 MB, any incoming messages will be returned to the senders.