We have several users getting the "Your Mailbox is almost Full" message that generates based on our quota enforcement policies. The problem is that after these users delete email from all folders including permanently deleting items from the 'Deleted Items' folder, the message still get generated and emailed to them. They still are not able to send or receive email even after freeing up space. What is causing this problem? Why are these users still not able to send/receive email even after the take the steps to clean out there messages?