When you delete an email message, the message is stored in your deleted items directory, unless you update this option.
You will have to login, go to the folders link and delete the email out of the Deleted Items directory.
Or a faster method would be to delete the Deleted Items directory completely.
Here are the instructions to update your settings in the webmail interface so that when you delete your email, it will delete it off the server instead of placing it in the "Deleted Items" folder on the email server.
Here is what you need to do:
1. Log into Webmail with the email address and password.
Click for Webmail2
Click for Webmail3
2. Click on the "Options" link next to the "Logoff" link.
3. Click on the "General" link.
4. Uncheck the boxes listed below:
5. Scroll down to the bottom of the page and click on the "Update Preferences" button.
Now when you delete your email out of your "Inbox" while your on the webmail interface, your email will no longer be on the server.