Have you gotten any bad messages or just have too many in the cbox? It is very easy to delete them. Just follow this tutorial and you'll see:)
Step 1: Log on to your cbox account. Then click Admin and then click on the Messages button at the bottom of the sitemenu.
Step 2: Here you'll see all of your messages, click on the little box next to the message you want to delete.
Step 3: When you have selected all the messages you want to delete click Delete.
If this helped, a link back is required.